antedeluvian

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Engineering Manager

Born and raised in what was then Rhodesia (now Zimbabwe), Aubrey Kagan completed his electrical engineering degree at the Technion, Israel Institute of Technology, and obtained an MBA at the University of the Witwatersrand in South Africa. He immediately started working in electronics and was fortunate enough to be around as microprocessors made their first inroads into industry. He was initially involved with designing controllers for industry and mines, with projects encompassing coffee packaging machines, railroad communication controllers, hydrological data monitors, automatic calorimeters, and diamond sorters. The isolation of South Africa (geographically, economically, and later politically) allowed him to gain a wide range of experiences with many aspects of the industry, including analog and digital circuit design, the use of PCs (including the use of spreadsheets) to gather data, and the early use of CAD. Aubrey now lives in Canada. Here he originally worked on the specifications for the Canadarm 2 (the remote control arm on the International Space Station), but he is now involved with far less grandiose projects. He is Engineering Manager at Emphatec, a Toronto-based design house of industrial control interfaces, signal conditioners, and switch-mode power supplies. Micro experience includes Intel (8048, 8051, 8080, 8085), RCA (1802), Zilog (Z80, Z8), PIC (16Cxxx), Scenix (SX18), TI (TMS7000, MSP430), and Cypress (PSoC1/4/5). His specialty lies in blending the linear with the digital hardware and then processing in software. Aubrey has written several technical articles for Circuit Cellar and has contributed several design ideas to EDN and Electronic Design as well as an application note for Cypress Microsystems. He blogs for embedded.com, Planet Analog and EE Times.He is also the author of "Excel by Example: A Microsoft Excel Cookbook for Electronics Engineers".

antedeluvian

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    • There are only five or so companies in the additive PCB printer business and no doubt quite a few more that use the milling machine approach. Is there a PCB printer in your future?

    • Everywhere you look there are switches- proximity switches, limit switches, activation switches, keyboard switches, and more. There are some convenient ways to interface to them when you are working in the industrial arena.

    • Having multiple LEDs flashing at different rates is not necessarily difficult.

    • Despite layout tools' check of netlists, a CAD design can include errors - normally as a result of human failing. A full check gives great benefit that increases the probability of getting it right the first time.

    • Driving inductive loads needs some precautions to prevent high voltage side effects.

    • A product is the sum of its parts, but the documentation does not necessarily reflect the same breakdown.

    • The creation of sounds to describe other phenomenon can be proactive rather that just audio conditioning.

    • We are electronic design engineers. We don't need to know how to wire our installations tidily. Or do we?

    • Over the years there have been many microprocessors/microcomputers that have been introduced. Some have never captured much market share for some reason.

    • I once worked on a diamond sorting machine. This is a description of how it works and some of the difficulties that I ran into.

    • There has been much written about the Red Pitaya FPGA-based multipurpose instrument, most of it positive. I looked to see if it would be suitable in a production test environment.

    • When you are a small organization with a varied customer base, there is no organizational way of doing things to complete a project successfully. Here are my suggestions for the things that you need to do.

    • Watchdog timers are all every well in monitoring and correcting the operation of wayward micros, but how do you protect against outputs activating or staying stuck active before the watchdog bites?

    • Timers are used everywhere and often you want to use a device that is stand-alone; that is without any host processor around. I will try to list all the timers and affiliated functions that I can find without a single programmable interface.

    • You might think that there isn't much room for individuality in connectors, but over the years I have come across some that don't run with the herd!

    • The probability that any product will fail is higher in the early stages of its life and also at the end of its life -- the so called "bathtub curve." How would you burn in your product to weed out the early failures?

    • Max's recent blog reminded me of what I'd like to use to help document my projects.

    • Whenever you design a device with a particular output, you have to debug and test it. What if your output is generic? How do you create a load that will prove that your design works?

    • Distributed electronics needs to be interconnected as well as powered. Sometimes it is possible to reduce the connection wiring to a single pair. After seeing a blog on the subject, I felt I could expand on the subject.

    • Distributed electronics needs to be interconnected as well as powered. Sometimes it is possible to reduce the connection wiring to a single pair. After seeing a blog on the topic, I felt I could expand on the subject.

    • Aubrey Kagan uses Silego's GreenPAK products to see whether a modern programmable mixed-signal array can replace a bunch of ICs in an old circuit design.

    • Have you ever made the mistake of believing what you were told? And has any of your work been destroyed by major natural event?

    • Engineer Aubrey Kagan muses about myriad aspects of embedded systems design and technology.

    • There are many approaches to flexible (i.e., versatile) connections, but it appears that European offerings are slowly taking over the market.

    • David " Is this showing the current in the driver transistor or in the load, or the voltage on the load " Actually it is the voltage on the load. The driver is one of those integrated things with built in short circuit protection and overcurrent detection. It's going in a small package and I need as much functionality as I can get. There is an external back EMF diode.

    • Elizabeth At least with this method you aren't dissipating power continuously through the resistor. Of course you do need a second supply. Was the second supply specifically for power reduction or was it just a happy coincidence that allowed for this approach?

    • Max The Mynah bird is also a great mimic of sounds. My mother lives in a retirement village in rather pleasant surroundings in Johannesburg, South Africa. There are many species of birds that flit around, one being the Mynah. One had learned to mimic the sound of a telephone ringing and would happily sit on the balcony and "chirp" at the crack of dawn, causing me to sit bolt upright trying to think who could be calling at that hour of the morning.

    • Max " So, will you be purchasing one of these little rascals? " We have one on order. Off hand I seem to remember delivery was towards the end of June

    • Since I wrote about keyboard scanning (although not the prime focus of the blog) I thought I should point out an app note I just came across using a Silego programmable part as a keyboard scanner http://www.silego.com/applications/keypadscanner.html

    • Elder " we are never old enough that we cannot learn new things " Too true. In my case it's the problem of remembering old (and not so old) things. "I would probably not think of looking for specific parts " It seems to me that a few years ago TI decided that the industrial market deserved some additional focus and it seems that it triggered sympathetic actions from other manufacturers. I have an upcoming blog on solenoid drivers where I think I see the same pattern.

    • David It's a long time since I thought about crosspoint switches. I checked on Digikey and they seem to go as big as 40x40, although between the price and the BGA, I am not sure you will be using them in a hobby application any time soon.

    • I like the serial interface, and the higher level commands, but for my money I would have preferred a 4th button. I did quite a bit of work with systems with hierarchical menus and it seemed that 4 buttons (up, down, back, & enter) was the minimum for reasonable user understanding of the system. I had to develop a whole approach to creating hierarchical menus especially when the customer kept changing his menus and displays every Monday and Friday. This was at a level of abstraction above the control commands for this product and could easily be implemented on this product. I wrote it up in an article in Circuit Cellar "Hierarchical Menus in Embedded Systems" in November 2003. http://www.cc-webshop.com/PDF-Issues_c51.htm (Circuit Cellar's business model requires minimal payment for articles and/or magazines)

    • From the first diagram, it appears that each PSoC has its own set of peripherals. Only some timers (undefined here), Flash and SRAM and IPC are shared. I presume that "IPC" stands for "Inter Process Communication", so there is a dedicated resource for the processor to processor communication. I wonder whether PSoC Creator will allow for both processors simultaneously or whether you will need to run two instances. Also of interest will be how they handle debugging two processors simultaneously. Cypress does not have a proprietary RTOS for the PSoC. It does support a few 3rd party OSs, but only for the PSoC5 and PSoC4. Will they add an RTOS for the M4 and/or M4 plus M0+ as component? As a long time PSoC afficianado, I am looking forward to the PSoC6 and I do hope it makes it to market soon- I believe I have an application for it.

    • My blog "MyScript Nebo vs. Notes Plus Handwriting Apps" has now been published http://www.eetimes.com/author.asp?section_id=36&doc_id=1331451 Please comment in either place with your experiences.

    • For those of you interested in another note taking app on the iPad, see Max's "The (Electronic) Pencil is Mightier than the Keyboard" http://www.eetimes.com/author.asp?section_id=216&doc_id=1331399&piddl_msgid=369113&piddl_msgposted=yes#msg_369113 I have written a follow up blog comparing the two. I will link to it when it sees the light of day.

    • @TonyTib "the CANOpen standard specified standard colors and flashing patterns for status LEDs. " Thanks for this. I didn't know that there were any standards for flashing LEDs. This is fascinating. If anyone is interested I found a description on P9 of this document http://www.leinelinde.com.pl/pdf/absolutne/CANopen_Manual.pdf Does anyone know of other standards? In coincidental way, I just got back from a customer who had implemented a partial CAN bus with a single LED indicator, and the whole system was crashing (hardware problem) and just flashing the LED.

    • Thinking about this, I started to look at the affiliated hotels. It seems to me that all 3 that are available require some form of transportation to get to the conference. It means that you can't just take a break and go up to your room to lie down (once you get to your 7th decade, this becomes a concern) like you can at ESC in San Jose. Does anyone know if there are any hotels at the conference site?

    • How's this? https://image-store.slidesharecdn.com/618bfbe9-2e2d-439e-b079-94eea386898f-original.jpeg

    • Here is another- the treadmill on my machine allows ~8 different languages BUT the legend on the button to allow you to select the option to change languages is in the language on the display. If you arrive and are greeted by something in Korean (I assume based on the flag icon) you have no idea what button to press to get back to English (or any other language) because everything is in Korean.

    • Hi Crusty It's been a while since I worked on the SPI and I don't remember this apparent anomaly. However, if I remember correctly the nature of the module (and SPI) is to allow simultaneously shifting data OUT to the slave on one pin whilst shifting data IN from the slave on another. They could probably write an API that was read only, but it would mask the fact that data would still be shifted out and if you had a scope probe hooked onto the output pin you would see data and be puzzled when this was an input instruction. Anyway that would be my guess.

    • Max Although your blog focuses on a complete product, I thought I should mention that I did a blog called "Niche Devices" over on Planet Analog on a bunch of specialist ICs, including a spectrometer device that may end up in these kind of products http://www.planetanalog.com/author.asp?section_id=3140&doc_id=564304

    • I am not the only one to rant about designs Max did it at lest once on "The best and worst alarm clocks ever…" http://www.edn.com/electronics-blogs/the-engineering-life-around-the-web/4237749/The-best-and-worst-alarm-clocks-ever- Martin Rowe did it on "Electronic products from hell" http://www.edn.com/electronics-blogs/rowe-s-and-columns/4443140/Electronic-products-from-hell There is a story from Robert Wessel "Stupid design decisions" https://www.embeddedrelated.com/showthread/comp.arch.embedded/218499-1.php

    • Paul Rako just wrote and interesting article "What’s All This 555 Timer Stuff, Anyway?" http://electronicdesign.com/analog/what-s-all-555-timer-stuff-anyway?NL=ED-001&Issue=ED-001_20170113_ED-001_372&sfvc4enews=42&cl=article_1_b&utm_rid=CPG05000002084443&utm_campaign=9246&utm_medium=email&elq2=4452959c79bc42fab348f66db7d9c259

    • I did try this by just entering the formula and I struggled to get anything to work. I managed to get just the year by going to Quick Parts| Field | Date | 1/11/2017 (or whatever the current date is) and then "M/d/yyyy" appears in the space below Date formats: if I edit the entry by deleting everything except the yyyy, it does seem to use the current year. Other than messing around with the PC's settings, I will have to wait till next year to see if it updates. It seems you can get similar results if you get to and then select the "M/d/yyyy" and then click "Field Codes", you can edit to just the "yyyy" and get the same result. Now that I re-read the blog, this does seem to be the process you intended.

    • @Fanl "Like Vala, but it would have its own standard library." Don't be modest. You should mention that you have written a blog "Vala Applications n Embedded Linux" https://www.embeddedrelated.com/showarticle/1019.php

    • As a comment to his blog "Do They Know that "Analog" Makes Digital TV Possible?" http://www.planetanalog.com/author.asp?section_id=396&doc_id=564478& Bill Schweber points out a link to good and bad examples of cabling: http://www.cablinginstall.com/articles/print/volume-24/issue-12/departments/infrastructure-insights/cabling-exceptionalism-order-vs-chaos.html%20 He points out that this is from a publication dedicated to the subject.

    • @Elizabeth "Better to find that you need a series resistor before you build the board. " Too true. I must apologise that all my stuff is written from a perspective of a small organization. It must be nice to have others around who understand and can contribute to your work.

    • @ Betajet Given my history of working with Excel, the thought occurs that maybe you could work a similar approach using it. Perhaps it would easier to manipulate and order the text. I once made a spreadsheet that loaded a microcomputer listing and then worked out execution times based on the instructions. You could even calculate either path in a conditional branch. Next time it comes up here, maybe I should look closer at the idea.

    • We have to do this as well in another circumstance. For reasons that I don't understand, some of or Chinese subcontractors take it into their heads that they need to modify the board. Is it a track that offends their sensibilities or some perceived improvement in production? Who knows? But if your PCB is UL approved not only shouldn't you change it without permission, you can't without affecting the approval. SO before any PCB gets made we get the gerbers back and we do the check you describe.

    • Thomas Thanks for the enlightenment. Welcome as a blogger. Will we see more of your very amusing writing style?

    • Thomas "Marketing: "Let's have the food news first..." (They are ever the optimists)." And hungry as well!

    • I just had a look at the Terms and Conditions https://www.andapt.com/?page_id=1492 Something to think about. Normally the IP is buried in the cost of a non-configurable chip. I am not sure I understand this model. It's a bit "Applish" since you are not allowed to write about the devices without approval. That puts pay to just playing around and blogging about it. It also seems that some, if not all of the devices carry a monthly licensing fee (if I understood it correctly). I need to wrap my head around this concept- I know it works like that with IP in FPGAs, but LDOs?

    • Looks intriguing. I poked around on the web site and of course it is all wine and roses, but there are quite a few products that are undescribed (look at battery chargers), so I suppose I will have to wait. An irritant is that you need to register before you can even glimpse a data sheet. I really don't want to be a recipient of more data when I don't know if I even want to see that data.

    • @Modal " I'd look at the footprints and insure they matched what I was expecting." YES! I am often guilty of failing to do this, and have suffered the resulting problems. Never assume! Also I often find Pin 1 markings of connectors and some other components are omitted. I like to make sure that the orientation is obvious to both the PCB assembler and the user who is connecting to the board. "When it comes to make revisions, I like to have a bullet list of what is changing" Another excellent point. After a revision how systematically should one check the new board?

    • @Sensatech "It is just do we have the time " Unfortunately it is true that many projects are subject to a time deadline. It is my contention that time spent before committing to a PCB design saves time spent afterwards, but a lot of engineers aren't afforded the luxury of a pause to review.

    • Gregorio "I also check part availability". Yes. absolutely. Because sometimes it takes a while between the design and getting the PCB made/populated, I sometimes even purchase stock of critical components.

    • @Manyosi Thanks. As far as AmellaMartin is concerned- it seems he/she/it posted the message elsewhere on embedded.com as well. Much as I dislike this at least I understand why when there is a commercial objective. Have you seen the inane and repetitive posts going on at Planet Analog? I have no idea what they are trying to prove.

    • Mark It's good to know that others have managed to approach and quantify this issue. It would be nice to find one of these kinds of documents in the public domain.

    • @Worknhard Thanks for the link. Although syntactically correct (as far as I can tell) it doesn't link to the document you mention. I searched for "Configuration Management" in the "Not Found" page and it shows up as the first in the list. It has some very interesting takes on the issues and I need to read it several times along with your comments to get it to sink in. But his looks like a GREAT starting point. At first glance it seems to me that in this approach there is no co-location of any item in the hierarchy and I suspect one has to put a lot of thought into this as to prioritizing schematic and PCB.

    • There's no question that you need a version control system. SVN and its ilk have the advantage that they only updates under controlled circumstances. However it appears to me that they require some form of network administration and in a small organization experience and resources may be lacking. In any event a version control system does not address how to partition the hierarchical structure of a product. That is where I am having the problem.

    • Elizabeth " You really need to have support for something like this in your tools though. And it really helps to have people who really know how to use the tools.... " Sometimes it's nice to work for a small organization and sometimes a few more resources would really be appreciated. I have to assume that your revision control system can handle these intermediate revisions. Is it included with Mentor Graphics?

    • @RGARVIN640 My electronic formative years were in South Africa which was far removed from any other epicentre of electronic design and the market was also significantly different. Intel had great representation followed at quite a distance by Motorola. Zilog and Synertek had the same representative and neither really did well although the latter was definitely the lesser. I know I had a Synertek data book, but I cannot recall even looking at it. It was all about support and development systems and it was all Intel at the time.

    • David There is no dispute about the influence of the 741- it just wasn't a direct influence on my designs. However indirectly it did influence me a lot. I did a design once for a coffee packaging machine that measured weight using LVDTs. The gain stage (designed by someone else) used 741s and they would drift everywhere, so I had to come up with a technique for calibration which was all very new at the time. My writing career started with that (remember the SA magazine "Pulse"?), and I actually have written about it again "How a Coffee Packaging Machine Educated Me" http://www.planetanalog.com/author.asp?section_id=3140&doc_id=563268&print=yes

    • @JackPeacock "I'd add the General Instruments AY-3-1015 async serial transceiver" I guess you'd have to add a Baud Rate generator to that. What part would you use- the Fairchild 4702? "lowly 2N3904 and 2N3906 transistors ". It didn't occur to me to include transistors, but you're right. They were a vital part of the arsenal- my goto part has been (and still is) the BC547, BC557 (BC847/BC857in SMD). This triggers the thought of the glue logic that was the foundation of it all- like the 74x373, 74x245 etc. Maybe there's another blog there.

    • All this presumes a universality of date. According to Simon Winchester (in his book "Pacific")until 1950 the Japanese all celebrated their birthdays on 1 January. In another chapter he points out that the North Korean years are counted from the birth of Kim Il Sung (1912) and so the year currently is a paltry 104.

    • To use a Zulu expression of farewell: Hamba kahle (pronounced "gashle")-go well. I look forward to still reading your newsletter.

    • @Traneus (rex) "The 6100/PDP-8 instruction set assumed that all RAM was writable and nonvolatile. Easy with core memory, but a bear with SRAM and EPROM. I read about EPROM boards with programmable holes for SRAM. Every subroutine was self-modifying code, as the return address was stored in the first word of the subroutine code." In my early days I was asked to evaluate the RCA1802 vs the 6100 since they were the only two CMOS micros available. I made the decision based on the bus width (more memory chips needed for 12 bits). Having rad this, I am relieved with the decision to go with the 1802.

    • @Robert Thanks for the addition. I see I have the data book in my scanned collection. See "Preserving Data Books From Yesteryear" http://www.eetimes.com/author.asp?doc_id=1320337

    • @Crusty Those rectifiers have a lot to answer for.

    • @NThanksForAllTheFish Sounds intriguing. Did your idea go anywhere? From your comment it appears that it wasn't accepted for your PhD

    • Max If the answer comes back to you, please let me know. I would love to read about it.

    • @Rcurl I just love FEELING those notes, on one pipe or many. I always use Bach's Toccata and Fugue to test out music equipment.

    • Duane A while ago I read a book on Lev. It's a fascinating story. He was sent to the US to ostensibly market the device, which he sort of did. But he was also using the technology to develop metal detectors and that got him into high tech establishments like Westinghouse and it was his mission to spy on them. There was an affair of the heart with the Theremin virtuoso, and IIRC he was rather taken with the luxuries of the west, but in the end returned to Russia. I am sitting in a hotel room in Montreal so it is a bit more difficult to provide links, but I encourage you to google the story.

    • Duane I be;ieve that one could argue that the Theremin "sonified" the position of the hands. I know you saw my blog, but perhaps others didn't. http://www.embedded.com/electronics-blogs/without-a-paddle/4442561/Sonification

    • Since my C has been self taught, I rarely get into more sophisticated constructs. I even avoid the use of pointers. I recently had to get into volatile declarations to stop the @#$! assembler optimizing out what I want. I often use dummy writes to a location simply as a place holder for a breakpoint. It gets optimized out and there is no breakpoint. Only today I thought I had found a bug in my debugger where the expected variable update did not occur until several instructions later. Tech support suggested making the variable volatile to allow for the variable to be updated at the right point during debugging, in order to verify correct operation. I think the compilers are now over-optimizing!

    • Bob "Commands Commands were not copied, but even so, the commands are no copyrightable because they are simple and descriptive of the functionality. Only creative expression that is not simple description and not functional can be copyrighted" I don't suppose there is a hard and fast definition of "simple and descriptive". As I recall Intel copyrighted the mnemonics to the 8080 Assembler. As a result Zilog had to come up with their own for the self same instructions.

    • I actually acquired a copy of CP/M with the intention of building my own computer. One of the problems in those days was there was no standard format for floppy disk drives. It shipped on 8" single side single density floppies in some IBM format. I never went ahead with it, probably because of an inability to convert to another format or acquire a suitable drive- I don't recall. If memory serves (mine, not the RAM), CP/M also had a restriction on changing floppy disks during normal operation. I remember thinking that this seemed rather unfriendly especially since this wasn't a problem on my Intel development system running ISIS. But I don't recall it being an issue on my Osborne 1 so perhaps they overcame the shortcoming (or my memory is faulty). Certainly MS-DOS never exhibited this shortcoming and the disk formatting was never an issue- other than the shift through single/dual sides and densities. But one disk manufacturer's drive was equivalent to another's .

    • AAh! Peripheral chips. That takes me back to the fun days of late 70s/ early 80s when there was a new peripheral chip every week. The excitement came in seeing what unique features each one had and whether it could be interfaced to your particular micro's bus. When Motorola introduced the MC16818 Real Time Clock they provide a MOTEL (Motorola/Intel combination) bus. Additional concerns was whether you could use the interrupt structure. Quite a few also had their quirks (I hate to say bugs). There were also component shortages from time to time. So it doesn't surprise me that some engineers opted for non-Motorola peripherals with a Motorola micro. The "C" in the part number suggests a CMOS part, so there may have been power issue as well. The "51" in 65C51 also suggests a link to the original Intel serial peripheral 8251. Maybe there is a blog in there ...

    • J just came across this e-book that covers some of the micros discussed, and some more "4- and 8-bit Microprocessors, Architecture and History" https://archive.org/stream/pstakem_gmail_8Bit/8-bit_djvu.txt

    • I only remember the AMD Am2900 bit slice family. I have the databook copied, but like you, I never actually used one. I think it may have been second sourced by Signetics. From my scans I see that Signetics had their own bit slice, the 8X02. Which reminds me of another micro that never amounted to much- the 8X300 from Signetics. According to the data sheet it was a 16 bit bipolar device. And at the other end of the scale there was the Motorola MC14500 single bit micro, which I did use.

    • Colin Aside from the factors that you list, I have found that documentation has deteriorated as chip complexity has increased. In my case I also look at the quality of tech support.

    • Duane "I did use the 1802. " I cut my teeth on the 1802, based around a Popular Electronics article which I believe triggered the ELF. I actually failed to use the registers to their full extent (being self taught, and I had a rotten teacher) an only came to appreciate them later. " I was dumbfounded at the limitations" I know what you mean and later after I had worked with 8051s Z80s Rabbits, 8080/85 8096, 80960 I got to work with the PIC 16C family (and Scenix). Dumbfounded is an understatement.

    • @TonyTib "Zilog also had a 32-bit Z80000 listed in a Zilog databook I once owned (but dumped a decade or so ago). " You mention of the Z80000 did tickle a vague memory. You may remember I did a blog "Preserving Data Books From Yesteryear" http://www.eetimes.com/author.asp?doc_id=1320337 I had a Zilog data book scanned, so I went to check and yes, it is there as a "preliminary product specification" and it does run to 49 pages of data.

    • Max All this talk of sounds being associated with acts, and how to the brain might interpret them brought to mind on of my favourite Goon Shows. Unfortunately it doesn't appear to be available in audio (for free) but here is the portion of the script of "The International Christmas Pudding" GRAMS: Loud dull thuds, continue under following conversation: MINNIE: Ohhhhhhhheeoh. What, what's that? What's that? Ohhh. HENRY: It's all right Min, it's just those noisy people in the tent upstairs. (calls) Who's that walking about upstairs? ECCLES: (off) I'm the famous Eccles! I got friends in. HENRY: He's the famous Eccles and he's got friends in, Min. (calls) Do you mind taking those noisy boots off? ECCLES: (off) OK. FX: Two thuds. MINNIE: Ahh, that's better. FX: Thud MINNIE: Ohh, I didn't know he had three legs, Henry. HENRY: He hasn't, Min, he hasn't, he has a one legged friend. Goodnight Min. MINNIE: Goodnight, buddy. FX: Thud. MINNIE and HENRY: Ohh! HENRY: He's got two one legged friends! FX: Thud. MINNIE: That, or one three legged friend, Henry. HENRY: Yes. Well goodnight Min.

    • Duane On the last photo you say about the 3rd connector "and a combined SMT and through-hole Type-C connector (upper right)," I know connectors are often through hole to give rigidity and for SMT they have mounting through holes as in the first two in the picture. I am not sure of the benefit of "combined SMT and through-hole". Have you any idea?

    • @Manyosi I wasn't aware there were any other diamond sorting companies in Johannesburg, let alone family owned ones. How interesting! The parent of the company in this project was the company that is always associated with diamonds. There was always money for research.

    • What I have noticed on US ads for medication is that the video image shows people living a wonderful life as a result of the drugs while the voice-over describes all the side effects up to an including death. Apparently the US rules (and I don't know who decides them) is there must be equal time devoted to the benefits and side effects. This is the solution. Canadian pharmaceutical ads have even more stupidity. You can name the product but can't describe what it does or vice versa. This has led to much creativity in the industry especially for products like Viagra. See https://www.youtube.com/watch?v=sMxIS7-94S0 or https://youtu.be/cMhv_wCx5ug

    • Max ". On a personal note, there's a set of traffic lights on my way home that are driving (no pun intended) me insane. They force me sit there on red for an unconscionable amount of time when no one is coming from the other direction. It would be a really great first step if these lights could see how many cars (if any) are approaching from the various directions and then change appropriately to achieve the highest possible traffic flow and the lowest possible driver frustration level." My councillor explained to me that the lights are often intended to slow the flow of traffic through residential neighbourhoods and around schools. That's the theory. I reckon it backfires because of road rage. It's one thing to bring me to a stop so that I go slowly. But why must I sit around for 2-3 minutes when there is no one else around. What about the air pollution created while I idle? So yes, I would love to see more intelligent traffic lights. Back in Africa we used to call traffic lights "robots"- maybe we were anticipating a level of intelligence. As for self driving- bring it on. I have much better things to do with my time than spending 40 minutes being alert avoiding accidents, staying under the speed limit etc.

    • Crusty The rail gun sounds really interesting. I don't think it would have occurred to me as a solution. a)How far were you able to launch the nuts b)how many buckets c)what was the granularity i.e. how far apart were the buckets, but I guess I could get to a rough answer from a) and b.

    • Crusty You have had a really interesting career. I would buy the book of your memoirs. On the subject of sorting machines, a lot of my experience was in a company that made radiometric sorters. The company changed modes and owners, and I sort of (unintended pun) tagged along , but was not really involved with sorters until this project. I was later involved with the initial stages of a sorter that involved microwave radiation of some ore (I don't remember what). For computing power I proposed the Intel i960 and I believe it was the first 960 development system sold in South Africa. For better or worse (or maybe both) I emigrated to Canada shortly after that, and so there is not much to re-tell on the sorting front.

    • Just to get an idea of distances and relative sizes see this NASA demonstration http://apod.nasa.gov/apod/ap120312.html?utm_source=May+2016&utm_campaign=May+2016&utm_medium=email

    • I should add that they "upgraded" the software on the cable box. Now if you select "record series (only new episodes)" it is incapable of distinguishing which is which so it records all occurrences of the program including past episodes. It recorded 9 instances of Vinyl every week. And there is no obvious way of even figuring out how to stop recording the series.

    • Max Your bedside clock wouldn't be a Sony would it? Your woes sound just like mine. Recording TV? Did you see my blog on "Made by Monkeys" called "Cable Box Causes Bigger Headache Than Daytime TV" http://www.designnews.com/author.asp?doc_id=276776 And I might add that they actually edited my complaints down by about a half. I had a go at the interface on machines at my gym in the same Made by Monkeys column- "Monkeys Got to My Cardio Machine" http://www.designnews.com/author.asp?section_id=1367&doc_id=212347&dfpPParams=bid_240,aid_212347&dfpLayout=blog

    • I didn't want to lose the data in all my data books so I scanned them all. I described it here Preserving Data Books from Yesteryear. http://www.eetimes.com/author.asp?doc_id=1320337

    • Iwill us this as a placeholder for more information on this topic: There is a design idea "Simple Circuit Communicates Over Low-Voltage Power Lines" http://electronicdesign.com/communications/simple-circuit-communicates-over-low-voltage-power-lines And there is also the KNX network. There are some ON devices that implement the protocol http://www.onsemi.com/pub_link/Collateral/NCN5110-D.PDF http://www.onsemi.com/pub_link/Collateral/NCN5121-D.PDF http://www.onsemi.com/pub_link/Collateral/NCN5130-D.PDF

    • @Pryderi "The Red Pitaya store and Elektor now offer pre-calibrated Red Pitaya boards." Yes, but... a) is there certification with that? b) what about re-calibration 12 months down the road. I know I did see a calibration procedure written somewhere in the documentation. Let's assume that it is comprehensive. I don't know of anyone who offers the calibration service- so I guess I will have to do it.

    • Max You may remember back in the days of APP, I mentioned my friend Leo, a 98 year old at the gym I go to. Well Leo just celebrated his 101st birthday. Still goes to the gym every day! Still drives and has a 79 year old girlfriend.

    • @Radio_Geek "You can get PRO apps, simply by sharing to Facebook." I am a dinosaur and I don't use Facebook, so I am not sure what you are sharing. Could you let me know what these PRO apps are. Are they any different to the apps in the Red Pitaya Bazaar?

    • David I must admit that I pulled my punch at the end since I thought that I did not have enough experience to pass comprehensive judgement and may have ended up having to change feet. On the other hand, I felt Dave also pulled his punch at the end with his overall recommendation. Neither of us tried any development and who knows maybe their documentation isn't up to snuff and tech support... Certainly our experience doesn't justify that conclusion, but we give them the benefit of the doubt.

    • Michael Dunn just pointed out to me that Dave has done an "EEVblog" on the Red Pitaya https://www.eevblog.com/2016/03/08/eevblog-858-red-pitaya/

    • Crusty Your budget may be "hobby" but your skills and experience most certainly are not. I would concur with your conclusion to look for an alternative.

    • David I started to list the surplus/hobby stores in Toronto. The weirdest was Active Surplus which had a gorilla on the sidewalk outside the walk up to the store. Besides normal electronics surplus you could get things like the left arm for a doll (no right arms!). But I just went to their web site and it looks like they won't be with us much longer http://www.activesurplus.com/ We have Sayal which is pretty good http://www.sayal.com/zinc/index.asp And more of a higher end hobbyist place is Active Tech (owned by Future) http://www.active123.com/ As a result of ownership issues several years ago, Radio Shack in Canada went independent and became "the Source" with much the same stock. But electronics stuff in the stores is a shadow of what it was (and it wasn't that great then!) http://www.thesource.ca/estore/default.aspx?language=EN-CA&gclid=CJ769p3MucsCFQ2QaQodO0IKMQ&gclsrc=aw.ds For computer parts/cables/connectors there is a great place near work. I don't remember its name and it probably doesn't have a web site anyway. And everyone misses Electrosonic's old shop. There is a new one, but the stock is now kept at Buffalo and I believe it isn't even worth a visit. https://www.e-sonic.com/

    • @TonyTib "which means I think you're out of luck" Sigh. The story of my life! " I doubt the Digilent Analog Discovery 2 is calibrated, either. " But I would hope with better functionality, with a searchable web site and tech support. Maybe also remote control of the scope and not just the acquired data. Enquiring minds would like to know.

    • "But perhaps most importantly, BASIC lacks the proper software engineering abstractions found in many other "real" languages." Firstly this is for writing an app on Android, so immediately there are restrictions on the universality of the code. As I droned on at the start of the blog, I really did try working with Java. It didn't work for me, not only because of Java itself, (although I found it incredibly verbose) but because of the development/support environment as a whole. Unfortunately, but adding spice to my life, the projects I get involved with vary from the application of an op-amp all the way through to the project that I mentioned, and there can be years between similar projects. During that time languages come and go. I don't need re-entrancy, polymorphism, or inheritance. The code is small enough that I don't need re-use, just copy and paste. I need something that gets me productive quickly and with minimal support. Basic does that. Can I develop in QPython for Android? Maybe there is a development environment for that. But why would I be any further ahead with QPython. I don't know about QPython, but Python itself has gone through incompatible changes in version upgrades. I have missed all in the time it has taken me to return t a project of a similar nature. As I mentioned, C# does show promise in that C# in Microsoft's Visual Studio will allow you to develop for Android. How well remains to be seen, and perhaps not by me.

    • And they keep on coming... I just came across a manufacturer I haven't heard of before- Custom Silicon Solutions. They have 2 products that would fit into this blog. First and foremost is the CS555 which is a micro-power 555 (sub 5uA current and down to 1.2V) with a twist. It has an internal 6 decade counter for REALLY LONG delays. The counter and its preset count is set up by an external programmer. There is the CS555C which is the above device with a built in precision capacitor. You can find their standard product range here: http://www.customsiliconsolutions.com/products-for-ASIC-solutions/standard-IC-products.aspx

    • I remember my first PROM programmer. It was built out of 4000 series chips with a RAM. Data entry was via a hex keyboard. The first time was the hardest, Afterwards you could read it back and modify it. There were no reassembles (it was all hand coded)- if you made a change you modified the code with a jump instruction and made the change in the new location, which probably included the instruction you had overwritten. The programmer was designed only for the bipolar 82S181 from Signetics. One day after temperature cycling the system stopped working. After much searching I discovered that one of the fuses had grown back. I had actually read of this in the magazines, but wrote it off as too far fetched.

    • Max "Causing people to have flashbacks is just one more service I offer " Could I ask you to add another service please. Flash forward is preferable to flash back, especially if you can let me have the winning lottery numbers in advance. I would be very appreciative.

    • Max I know you got a blog out of it, but do hope Ryan is appreciative of the time you put into it. I agree with all that you say and as you were saying it I could see images from the past scrolling across my mind's eye. Since Ryan appears to hack the "knack", I don't think you will have discouraged him from becoming an engineer, but I hope he realises the benefits of bootstrapping. Although it helps to know where you came from, it's where you are going to that matters.

    • max "Can you imagine seeing the gears slowly turning, illuminated from within by flickering red light." This conjures up images of two movies with humans tied u in the gears, although the first "Modern Times" was in black and white. The second was "The Hudsucker Proxy" where time s stopped by jamming the gears of a clock. Both excellent movies. And something in the back of my head has gears and clocks in "Hugo". Do you remember?

    • Max " is actually an antique fire extinguisher sprinkler head. Who would have thunk?" I recognised it immediately having worked in the industry for a while. See my recently revived blog "Unintended Consequences" http://www.planetanalog.com/author.asp?section_id=3140&doc_id=564142&

    • David "and glad at least one person reads my blogs :-) " I know what you mean. About two weeks ago I was this close (picture my thumb and index finger about a mm apart) to giving up writing blogs. Sometimes when I give a URL I use bitly to create it. It gives me a count of the number of times the link is clicked. I Inserted one in the last paragraph right at the end. Now I can't tell you how many times this blog has been accessed so that you could get an idea for your own, but I can tell you that 39 people so far have read the blog to the end and clicked on the URL to my comment in another blog. The link to my worksheet in that blog has been accessed 58 times. Now I know that that DI is very popular from when it was first published (it was selected as one of the top 5 DIs that year and elicited very positive comments) and yet no one has posted an answer to my comment. Bottom line. Keep writing- people are reading your stuff. Like you though I do wish that they would post comments more often.

    • Max Years ago I wrote an article on "Hierarchical Menus in Embedded Systems" (in Circuit Cellar issue #160, November 2003). Now to rephrase one of your sayings, I am up to my crotch in crocodiles so I can't compare techniques. Mine was for a system with a character based display 32 chars x 4 lines with maybe 30 different screens. It was easy enough to create it the first time, but after the 3rd time the customer changed his mind I had to come up with a way to change it easily. I adopted a tabular approach with every screen having a identifier and every line having an identifier as well. For every line there were identified processes that could be executed to display parameters and measured readings as well as the next screen if that line was selected. And every screen had a return screen. Any time a screen was needed the processor fetched all the parameters from the table and created it. In fact I then developed a way in Excel to display what screen the current screen derived from and where it would take you to. The method is very similar to the project management worksheet I referred to in my comment in "Software Standards Compliance 101: Using a formal requirements capture process" http://www.embedded.com/design/safety-and-security/4441129/Software-Standards-Compliance-101--Using-a-formal-requirements-capture-process

    • I sometimes use the line in job applications "I have designed for devices 300 miles above the earth's surface as well as 2 miles beneath." No wonder I don't get any offers.

    • David "there are plenty of embedded systems up there keeping it going – have any readers been concerned with those?" Well yes, I have. I worked on the Canadarm2 (correctly called SSRMS), the robotic arm on Space Station Freedom (as the ISS was called back then). I was going to write a long response, but as I am looking for blog topics, I want to thank you for providing the idea. You should watch for it in the near future. Before you think everything is upbeat and wonderful in that world- let me quote you the last line of my blog "I was once a rocket scientist and it wasn’t all it was cracked up to be."

    • Max I, like you could do with training with in many aspects of programming, C++ and Java (especially when I was working with Android) but who provide courses within the necessary slant towards electronics and control. If you don't have the slant then the learning curve is much steeper, and fraught with issues since you have to learn from your mistakes and not be example. I might add though that I think your example falls into the C obfuscation trap. variables. Based on this, I'm used to creating for() loops like the following: " for ( i = 0; i LT 10; i++ ) { // Do some clever stuff } for ( i = 0; i LT 10; i++, j-- ) { // Do some clever stuff } adding the j-- there does not make the code any faster and hides the action for some giving the code a glance over. It would be far more understandable with the j-- within the curly brackets. But then I am a C neanderthal. PS, you will note the LT rather than the less than symbol- apparently I can't use the less than are greater than symbol in a comment. Yet another dislike of the embedded implementation of a forum

    • I use an "atomic clock" something like this one http://www.amazon.ca/Crosse-Technology-WT-8005U-W-Atomic-Digital/dp/B002VRUN2U/ref=pd_sim_sbs_86_1?ie=UTF8&dpID=41KZmw4nZqL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=0Y2T2RBGKYD0MJGH2HXR

    • There are tools to create a traceability matrix, but if you have none available you can use Microsoft Excel to create one. I published a design idea in Electronic Design entitled "Use Excel To Develop A Traceability Matrix" http://electronicdesign.com/embedded/use-excel-develop-traceability-matrix Unfortunately ED no longer seems to provide access to the Excel file. You can find it here: http://bit.ly/1Pceza6

    • Max I have noticed several similar effects, but they don't impact my life quite as badly as they do to your friend. My friendly cable provider will occasionally get the sync so far off that the dialog is completely out of sync wit the characters uttering the words. If I have my TV sound on along with my sound system there is a noticeable echo. If I remember correctly, the problem existed even in the good old das with both analog cable and DVD player. Sometimes I watch the same show upstairs that my wife is watching downstairs, the sound mismatch (of course there is probably a visual mismatch as well) can be several hundred milliseconds (if not more) and is distracting enough to necessitate shutting the doors.

    • "Have you seen those glass walls you sometimes find in posh showers at posh hotels? You flick a switch and they go from being transparent to opaque." The windows on the 787 "Dreamliner" work like that as well.

    • Max This is remarkable. Years ago, when I was in school, a friend and I made a scene of a mine for a school project. It looked awful as only the work of two unruly 11 year old can be and I appreciate the detail that has gone into this. My friend's father took one look at our project and redid it using your techniques and it looked really good. The project won 1st prize and I learned the lesson that to win a prize you need to let someone else do the work! By the way, how did you decide on the 1/32 scale. How does anyone decide on a scale- who decided the scale of the Hornby double-O or the Lionel or the Airfix kits (1/72)?

    • Good eye! Rule #16- get someone else to read your documents with a critical eye.

    • Max Although it is a small country (only 300Km long) there is quite a bit of visual variation including the snow covered peak of Mt.Hermon in the north-east to the hills of Mount Carmel around Haifa on the Mediterranean. On a clear day, Mt Hermon is visible in the distance some 60 or 70Km away (this is the width of the country at that point). There is the coastal plain stretching down to Gaza, and the Negev desert with the mountains of Jordan in the distance (location of Petra) reaching down to Eilat which has a great coral reef. However Jerusalem is in the Judean wilderness and so you have to find beauty in he desert scrub and olive trees covering the hillsides. The South Africans always said that Johannesburg is the only major city in the world not built on the coast or a river. I don't know what the definition of a major city is, but Jerusalem falls into the same boat (if you can say that about a place with no major source of water!).

    • In the book "The Yiddish Policemen's Union" by Michael Chabon, he develops on the idea that the State of Israel was not created in the Middle East, but in Alaska. Turns out there really was a proposal to do that. Outstanding book, by the way, but it probably helps if you have a Jewish background. The book "Pope Joan" by Donna Woolfolk Cross creates a story about a female Pope. Turns out there is quite some evidence for this. Not a very good book though.

    • As I recall there were some ICs that were 0.4" wide. The Intel CMOS RAM 256x4 5101 was one. HP (now Avago) have an 8 pin DIP package that looks like it swallowed some steroids. Look at the HCNR-201 (http://www.avagotech.com/docs/AV02-0886EN). Actually there seem to be a few subtle variations on standard packages when it comes to optoelectronics. I have been stung at least 3 times. Also on some SPI EEPROMs (from Atmel IIRC).

    • And who could forget the TI 2716 which, unlike the industry standard 2716, consisted of two 2708s (multiple supply voltages) that you could see side by side through the erase window. When TI brought out the single supply 2Kx8 EPROM, they numbered it the 2516.

    • When it comes to power ICs often there are extensions made to the TO-220. Take a look at the L6203 (http://www.digikey.com/product-search/en/integrated-circuits-ics/pmic-full-half-bridge-drivers/2556632?k=L6203).

    • From my early days I remember these transistors that had these "wing" pins that we mounted just like Surface mount today. I think they were called "beam leads", but although I can find reference on the Internet, I can't find photos. There is a beam lead diode on Digikey, which looks similar http://www.digikey.ca/product-detail/en/MA4AGBLP912/1465-1016-ND/4429520

    • David Nice trip down memory lane. Two unusual IC types that I recall were 1) the piggyback EPROM on a microcontroller as described here: http://www.cpushack.com/2011/03/06/cpu-of-the-day-ns87p50r-6-piggyback-cpus/ I actually still have one of these. 2) the "snaphat" battery backup/CMOS RAM combination. These are still available in both through hole and surface mount see here http://www.st.com/web/en/resource/technical/document/datasheet/CD00000542.pdf although I believe the idea was pioneered by Mostek which ended up at ST via several iterations. It think Dallas Semi (part of Maxim now)also made something like that IIRC. Several rumours on the takeover of Maxim now.

    • These appear to be similar to many connectors made by several European connector manufacturers. I believe they are an industry standard format. In fact if you look at the D-sub connector I refer to in the article (P-Q3-B3RX) you will see it uses the same outer shell. Wieland makes a quality product, but I am unqualified to judge as to its relative standing.

    • If I can paraphrase a childhood ditty: Weidmuller's orange dilly dilly, Phoenix is green Entrelec's blue dilly dilly, Wieland is white, Wago does beige dilly dilly... Since my employer is no longer Weidmuller the corporate fashion scheme has evolved into black connectors (albeit still mostly Weidmuller) and black solder mask. (The solder mask makes trying to follow traces devilishly difficult.) So not only is the orange/green scheme self identifying, it is also self dating.

    • I presume that if you can write a .csv file, you can probably read one as well. In that case you could download a good packet and then fiddle it within Excel to a bad packet which would probably be a lot less painful than starting from scratch.

    • As I said flavour of the month. I just came across another Time of Flight sensor from ST, the VL6180 http://ca.mouser.com/new/stmicroelectronics/stm-vl6180-flight-sense/ Each seems to be aimed at a different market, but the group name must have a good marketing ring to it.

    • Seems that Time-Of-Flight is the flavour of the month. I just came across The ISL29501, Time of Flight (ToF) Signal Processing IC http://www.intersil.com/en/products/optoelectronics/proximity-sensors/light-to-digital-sensors/ISL29501.html?mkt_tok=3RkMMJWWfF9wsRokuaTNZKXonjHpfsX66%2BwkWaeylMI%2F0ER3fOvrPUfGjI4ASctnI%2BSLDwEYGJlv6SgFSrTBMbp4wLgKXRA%3D

    • I was going to offer max a bunch of 24V relays (I do work in industrial interfacing), and throw in a 24V power supply. There are LED indicators, but most of the relays are the opaque orange or black ones. Sorry Max. We are going to have to wait for your impecunious state to transition in more prosperous times. Maybe I should write a blog, but I only know one trick to make the relay latching. It would be even more dull and boring than my regular blogs!

    • Max thee certainly are some gems here. I have always believed that there was a need for a course/book called "Finishing School for Newly Graduated Electrical Engineers". I think these could be the basis.

    • I must admit that 55pS times seem to be way out of my league. According to the data sheet "This accuracy makes the TDC7200 ideal for application such as flow meter, where zero and low flow measurements require high accuracy in the picoseconds range." Probably a whole lot more meaningful if you are involved with this kind of thing. However I intend to keep the idea in my arsenal, I have needed to measure "time of flight" in the past and it involved quite a few ICs. Perhaps this would have made it simpler.

    • It is a long time since I visited Copenhagen, and I am jealous! Aside from Danish design, the thing I remember most were the instruments of torture at the National Museum, IIRC. There was a rack, thumbscrews and an iron maiden and more.

    • Max "(for some reason the cable controller can't handle the TV's volume)" I have similar problems with the controller on my cable box, not to mention another which always leaves the TV and the box out of phase- one is on t'other is off. In my opinion the whole PVR/cable box is very poorly designed. I did a piece for Made by Monkeys on my issues "Cable Box Causes Bigger Headache Than Daytime TV" (http://www.designnews.com/author.asp?doc_id=276776&dfpPParams=ind_184,industry_consumer,kw_33,bid_240,aid_276776&dfpLayout=blog ). And Design News actually edited down my litany of complaints!

    • When VCRs started becoming popular ~1987 the ones I had always had a wire remote control. Some TVs at the time had the ultrasonic remotes, ours had none. Keep in mind TV was only introduced in South Africa in 1975. Quite often we would trip over the 15' cable. We actually had at least 3 VCRs between '86-'89. We never had to worry about service or repair, we kept having burglaries and so they got replaced frequently. Only the last one was cordless.

    • Max At the risk of adding to your stack of controls in front of the TV- you do know Apple has an app that allows you to use your iPad and/or your (actually somebody else's, since you don't have one) iPhone as a control for Apple TV and other Apple devices. I recall a different name, but it appears to be called somewhat intuitively "Remote" (https://www.apple.com/ca/support/appletv/remote/ )

    • David Nice description, but I dread where all this may go. Perhaps there will be something like Max's Inamorata Prognostication Engine- take a photo and Google tells you what he/she is thinking.

    • I should also mention that there is an analog technique to read multiple switches on a single analog input. One approach (and there have been many design ideas over he years) is described in this recent design idea "Read multiple switches using ADC" http://www.edn.com/design/analog/4439796/Read-multiple-switches-using-ADC

    • Sounds like you and Steve (Manley) ahave a head start on the idea. You just need to change your cubes to spheres. Perhaps just with RGBLEDs on the surface. Then enlist Duane to figure out how to make the PCB! Actually sounds like a suitable project at the AutoCAD AIR facility- did you see Ransom Stevens' EDN article on it? http://www.edn.com/electronics-blogs/measure-of-things/4440038/Measure-career-advancement-by-blowing-your-mind?_mc=NL_EDN_EDT_EDN_weekly_20150806&cid=NL_EDN_EDT_EDN_weekly_20150806&elq=9ece1859df3f4ae6a6b536faa8f48f83&elqCampaignId=24260&elqaid=27401&elqat=1&elqTrackId=0df716c1a79e4725a783701f7e30b209

    • Max Like you, I am a self taught C programmer. No doubt there are many flaws in my approach, but what I would have done would be to create two arrays. The first contains the total number of dots and dashes for each character. The second would be the bit pattern with a 1 representing a dot and a 0 the dash. Like Cdhmanning, I would also reflect the array, with the first bit to be transmitted, not in bit 0, but bit 1 to simplify the program. The iteration of my program would be to load the number of bits from the first array into a counter and then shift the concomittant byte (with dot/dash pattern) from the second array right (hence putting the LSB in bit 0), read the 0th bit and transmit the dot or the dash depending in its value. When the timer has elapsed, decrement the count (i.e. still dots and dashes to be sent) and if not zero, repeat from the shift.

    • A possible alternative to the Hypertronics connector (I don't thnk it has anywhere near the number of make/break connections), but perhaps quirky in its own right are the power jacks and plugs from Switchcraft- http://www.switchcraft.com/ProductSummary.aspx?Parent=1074 Just what "Automatic switch over from AC to DC permitted by sleeve shunt spring" means is a puzzle to me at the moment..

    • You also make a very important point (Point 2) that I should have mentioned in this or the next blog. The frequency of the multiplex sequence and/or the rise/fall times of the output pins can generate EMI. It is best to keep that in mind from the outset of the design.

    • "your 44labs [sic] " Damn autocomplete! I am surprised no one picked up on the autocomplete in my post below, where it changed "Racal" Electronics to "Racial" Electronics (especially since it was in apartheid South Africa) .

    • Thanks for this. I missed the touch tone revolution as South Arica lagged in its introduction. When I got to Canada it was fait accompli. I tried to Google the topic, but I can find no description of the technique. Do you know of any? I am guessing an old time data sheet somewhere covers it.

    • Max Years back, before Windows, AutoCAD had drivers for different digitizers. I was using a Bit Pad One. I think I still have it somewhere in my basement. I must say, I struggled to adapt to the mouse afterwards. The stylus was a pen-like object with a tip like a ball point pen. Of course the cursor followed the motion of the stylus around the "pad", and selection was by pushing down on the stylus point. Seems awfully primitive compared to what you describe here. I wonder if the world will move back?

    • Max I have a water softener in my basement. The smallest bag of salt weighs 44 labs. Dragging 4 or 5 bags from my car, up a flight of 4 stairs and then down a flight of about 12 stairs always does a number on my lower spine with resulting visit to the chiro. I tried to suggest smaller bags to Culligan and Home Depot to aid an aging population, but so far, nada. It seems to me that I might go for a variation of the wheelchair that would allow me to wheel the bags without hurting myself.

    • Max, The balancing wheelchair brought back a butt-clenching memory. In my first job at Racial Electronics in South Africa they had a disabled guy in the quality department. He had mastered the art of leaning back in his wheelchair and balancing on two wheels, but NOBODY TOLD ME. The first time it happened, I tried to jump forward to catch him. Fortunately I never made it, or I might have actually knocked him over. Actually, thinking about it, maybe it was a form of initiation. I still cringe, 39 years later.

    • There is also the reverse effect where the LEDs an a single bar change as you move it across so you can read a compete line of text-Rich Quinell showed one at last year's San Jose ESC (whatever it was really called) at the Fantastical Theatre

    • I have 4 multimeters at home: 1. an analog Kaise meter. It has been surprisingly robust, these 40 years. 2. FLuke 8020A. Also has held up well although the plastic is yellowing. The user manual also describes how to measure the forward gain of transistors. 3. Non Linear Systems Touch Test 20. I got this as a return from the distributor when NLS discontinued the line. The lead-acid batteries had died and was pulling down the power supply. I removed them and had to add a big electrolytic capacitor to get it working again. 4. A Radio Shack 22-812 from 2002. I bought it because it was the cheapest DVM with a serial port that I could find, and I needed it for a chapter in my book which describes loading the reading directly into Excel.

    • David Ah yes, Hamrad- as the name suggests, they specialised in ham radio. I remember going to their store in downtown Johanneburg, and in fact I later worked with an ex-employee. Their moves seem to have mirrored the changes in South Africa. They moved from downtown JHB to the suburb of Wendywood in the 90s. I guess they always had a branch in Cape Town, but from the web site, it now appears that that is their only location.

    • David We have many DVMs running around work. Most are long in the tooth, and the most popular re the Fluke 8060A. This is certainly my favourite DVM and the only problem I have with it is that it is a 4 1/2 digit device. When measuring a 4-20mA loop, it is nice to have 3 digits after the decimal point, but as you get to 20mA it goes into an overload condition and you have to change the scale. And it uses a different shunt, so the reading is not a linear change. For instance 19.995mA on the greater resolution becomes 20.01mA on the lower. Recently (in my world that is about 5 years ago) we got a few Agilent U1251As which are quite nice and I think are rates 4 3/4 digits so the 20mA rollover isn't an issue. But it does have one thing that irritates me- the automatic shutdown is time based, so irrespective of how many reading you take and how those reading vary- every n minutes you have to push a button to wake it up. I know, I know, you can shut off this option, but it sort of defeats the purpose. I have at least 3 multimeters at home, including an unusual Non Linear Systems one, but I will have to wait till I get home this evening to document this.

    • Max There was a very good movie recently (2012) called "Robot and Frank" (http://www.imdb.com/media/rm2489821696/tt1990314?ref_=tt_ov_i) in which a senior citizen trains his robot helper to be a cat burglar. I enjoyed it immensely, but don't look at the plot on Wikipedia- it gives it all away!

    • Jack Since I have already done this as a profile it's easy to open the discussion by pointing at it. http://www.embedded.com/user/antedeluvian

    • I looked further into the list- there re some great ones, but the on I found the most amusing was: Beauty: Helen[edit] Main article: Helen (unit) Helen of Troy (from the Iliad) is widely known as "the face that launched a thousand ships". Thus, 1 millihelen is the amount of beauty needed to launch a single ship. Other derived units such as the negative helen (the power to beach ships) have also been described.

    • Max When I was in university in Israel in the early 70s, they followed what I believe was the European terminology- a milliard was an American billion and a billion was the English billion.

    • Elizabeth Thanks for asking the leading question. My next two blogs are on multiplexing, in July and August.

    • Tony I think you should be writing some articles on connectors as well! I remember that you also had some valuable input in the blog I referred to at the beginning of this one.

    • Max "Another question involves modelling the waterfall and the pool." The best I can come up with is fine tinsel (like the stuff that used to be on the paper tray on printers) behind some clear polyethylene. And then add a mild breeze.

    • I also think that they could have provided some basic hints, like the capacitance diminishes as you approach he rated voltage and how it relates to frequency, and they seem to miss (or I didn't see) any discussion on the thermal effect in resistors and capacitors

    • If it were up to me, I would've added a difference amplifier circuit to the amps, even if there was nothing on instrumentation amplifiers. There is a circuit (Fig 40) for an IA input filter though- that is quite useful. It strikes me that the op-amps section doesn't deal with any single supply operation Funny because TI has a great app note on that: SLOA030A Single-Supply Op Amp Design Techniques http://www.ti.com/lit/an/sloa030a/sloa030a.pdf

    • David Like you, I also got the email notification and I agree with you assessment that it is a worthwhile addition to my reference material. I think the title is a misnomer though. I really doubt that even at reduced fonts it would comfortably fit in anyone's pocket if you did want it in paper form. Maybe a cargo pants' pocket. I prefer my stuff in printed form and so I did print it out and put it in a binder with tabs an it sits right above my desk Since I am chained to it (the desk that is), the "pocket reference" doesn't go anywhere.

    • David "do you remember the old Mercury-wetted contact relays beloved of teleprinter comms designers?" Yes I do. I also remember mercury switches that I used to use for a snooze button on a few alarm clocks that I made for friends. I actually seem to remember considering an inclinometer made out of mercury level sensors (for use in levelling some mining equipment). I also remember playing with the mercury from broken thermometers and "plating" copper pennies so that they were silver. No to mention playing with mineral asbestos. Aah, the good old days!

    • David Another issue not mentioned much in data sheets is that connectors often have a minimum current rating (like the wetting current in relays) and below that your current may not flow. And if you think some of these connectors are rare, try and get them with gold plating!

    • David I recently had this problem with my year-old air-conditioner unit at home. It was under warranty so I didn't try and solve the problem. It was replaced by a brand new board.

    • Just today I got a newsletter from Digikey also now stocking the TE Ariso range. Quite pricey, especially since you need a pair! Both Mouser and Digikey carry links to more detailed data sheets.

    • I found a datasheet online for the Hypertronics Y series here: http://www.datasheets.pl/connectors/Y_SERIES.pdf

    • "These days it is really hard to find someone that does Basic and any work you do cannot be used in the future - since Basic is not portable. Try python..." Notwithstanding that it is my intention to get into Python in the next few months, I am afraid I can't agree with you. Any technician I know has had no trouble adapting to BASIC.I cannot see them getting into any other language as quickly. The Basic in this case is always implemented on a PC and so far it has worked on every version of Windows. The idea is to get a functional tester ASAP without turning the guy into a programmer. I don't plan to be in the industry for another 10 years, but I would be willing to bet that there will be no Python in 10 years, but there will still be Basic. In fact having completed an app for Android written in Java (http://www.planetanalog.com/author.asp?section_id=3140&doc_id=561592 ), I was so disillusioned with it and the UI that I intend to switch to using Basic4Android (http://www.b4x.com/b4a.html) for my next project.

    • Max "When the circuit board is powered up, the Zynq's hard ARM Cortex-A9 microcontroller subsystem is automatically ready to rock-and-roll." 1. is there flash for the processor already on the Zynq? 2. I am not sure if I am reading this correctly- is there hardwired code included in the Zynq to allow for the processor to fetch the the configuration from some non-volatile memory (internal or external), or do you have to write this yourself? 3. If it is predetermined, is it possible to modify it if you decide to take a non-conventional approach to a design?

    • Max At the risk of subverting the train of discussion here, the Cypress PSoC1 has the ability to dynamically reconfigure and the functionality is built into the UI, PSoC Designer. I have used it quite effectively when I have needed additional resources. In one case on a Modbus slave, I wanted to speed up the CRC calculation rather than execute it in software. Since the UART was not operational during the CRC calculation I could reconfigure the blocks used for the UART to a hardware CRC generator and then back again. For some reason Cypress hasn't allowed for this in the UI (PSoC Creator) for the PSoC3/4/5. Recently I would have liked it on the resource limited PSoC4. Sigh- win some, lose some.

    • Ken Good detail although there are alternate ways to drive the thermistor. Something to note is that the circuit in Figure 2 reduces the dynamic range of the ADC, something that may be of concern if you only have an 8 bit ADC available. Might I add that I did a series on temperature measurement, albeit at a higher level of abstraction, originally on Microcontroller Central and transferred to Planet Analog http://www.planetanalog.com/author.asp?section_id=3140&doc_id=562649 http://www.planetanalog.com/author.asp?section_id=3140&doc_id=562780 http://www.planetanalog.com/author.asp?section_id=3140&doc_id=562851 http://www.planetanalog.com/author.asp?section_id=3140&doc_id=562878 http://www.planetanalog.com/author.asp?section_id=3140&doc_id=562879

    • David I have done a bit of work with Visual Basic and even before it became a compiler, it still required a fair setup and quite a bit of knowledge on programming. It is also devilishly difficult to document because it is even driven. We had and still have several technicians who had programmed test procedures using MSBASIC and the FT-100 (http://www.y-tek.com/index.php?option=com_content&view=section&layout=blog&id=4&Itemid=2 ) "functional tester". At the time there was a misconception at our place the FT100 had been discontinued. It also suffered from several shortcomings in that you download the code from the PC to the unit and so even the minimal debugging facilities embodied in MSBASIC were lost. It also was I/O limited. As I mentioned in the blog I initially developed a hardware I/O system, based around the RS485 I/O modules and Visual Basic for a fairly sophisticated test jig. But as I have also remarked in earlier blogs, anything you design in a small organization remains an albatross around your neck for as long as you work there. I wanted to allow our existing and newer hires a quick and easy way to start and develop in a BASIC interpreter. At the time I landed on BBC BASIC. It was inexpensive and had some graphics capabilities, although my original idea was not to have anything fancy, just a menu driven application. But there was no way to restrict one of the guys. There were (and maybe still are) some other BASIC interpreters. I never managed to evaluate them.

    • David Not to worry, I'm pretty sure the world knows I make mistakes. As to correcting/removing posts it is one of the many improvements I would like to see on embedded.com, but will it happen?

    • Dougwithau Sounds a lot like an early environmental chamber that we built (obviously only for elevated temperatures). We also put a thermistor on a bang-bang temperature controller to try and keep the temperature constant.

    • Hi Crusty "Have also used a bank of modified standard domestic fan heaters " WE actually designed the system to use three or four domestic fan heaters to help boost the ambient temperature. They proved to be remarkably fragile, dying every Monday and Friday- fortunately the self heating of the power supplies proved to be sufficient, and so we gave up on the additional heaters.

    • Steve I am always astounded at how great your stuff looks and the workmanship that goes into it. As always the video is of professional quality. And you just whipped it up! I look forward to your next blog.

    • Jack I don't dispute the stability of the Office products, but I am far from happy with the abilities of Word (less so with Excel). On a feature by feature basis Word has everything that the competitors have (or had), but try to get them to work together- for instance, try and get automatic numbering to work in a table. Or tyro copy nada pasting with automatic numbering with bold formatting and see how quickly everything gets confused, and how do you reverse it all to get what you want. I wanted to do a series of blogs called "Dear Mr Gates..." pointing out all the problems that I had found in Word. My editor at the time didn't go for it.

    • Ivan I liked the graphic effects, especially the way the light bar pushed the seconds around the dial. I did find some difficulty in identifying that the time was 9 hours. I assume that each LED in the 12 LED circle and then the 24 LED circle was uniquely associated with an hour and I also assume that the orientation in the clip was not that of a clock on a wall. Maybe I am seeing it wrong.

    • Ivan "One down-side note to mention however, is that whenever the supply draws more than a few amps, it ‘sings’ a bit," I once designed a fairly cumbersome piece of equipment that would hum most of the time. It didn't know the words- Ha! Ha! I borrowed a stethoscope from a Doctor friend to try to localise the sound- didn't help in the slightest. I seem to remember that I discovered in the end that it was the linear power supply, but the tone sounded higher than 50Hz, so I am still not sure.

    • "'Alt PrintScreen' is your friend." Did you know that there is a "Snipping Tool" shipped together with Windows at least from Windows 7 (in the Accessories on the Start button in 7- else where in 8), although it may even be in XP. It allows you to highlight, add coloured pencil type markings (forget about actually writing) and erasing, saving to file in several formats, obviously along with capturing a window on the screen. In the same folder, there is also a Math Input Panel which allows you to enter mathematical symbols/equations with a mouse (or touch if you have it) and then recognizes the input and converts it to text which you can paste here you need it. Needs improvement. There is also a "Sticky Notes" app that will allow you to plonk yellow notes all over your screen, which you can also cut and paste. There you have it- three more friends... well maybe more like a friend and two acquaintances!

    • Ivan Apropos of your comment "Lastly and obviously, no clock would be complete without a time-keeping mechanism, so a clock/calendar is included." See this Conan O'Brien piece about the iWatch and telling time. https://www.youtube.com/watch?feature=player_embedded&v=tQPJSaiNS-Y

    • Reminds me of a vaguely amusing story of Zimbabwe (actually it was still Rhodesia then). In the "thriving" town of Gwelo (now Gweru) there was a single traffic light ("robot" in southern Africa) in the middle of town. In those days it was the lights mounted on a pole in the centre of the intersection. One night an impaired driver crashed into it and knocked it over. The council then voted to remove it completely.

    • Oops- the link to "How Well Can You Work With Others?" should be http://www.eetimes.com/author.asp?section_id=36&doc_id=1324832

    • Essentially what I want is a blank notebook. I would like to be able to link to and/or include "parts list, schematic, or the code" as well as the specifications, but I don't see any of these forming the base on their own. I just want to document the whole design phase which includes ideas, discussions, meeting minutes, decisions, sketches, tests, DFT thoughts, problems and solutions- anything that you may need to remember. "Share" is a difficult word. If you mean joint product development, I did cover some of that in my blog "How Well Can You Work With Others?" (http://www.embedded.com/electronics-blogs/without-a-paddle/4439509/The-app-I-need ), but that's not what I had in mind for this app. The contents, or maybe part just of the contents, could be shared with colleagues, ISO auditors, perhaps attorneys (patent or otherwise), design reviews, performance appraisals and whenever you need to refresh your memory.

    • I forgot to mention (although it should be relatively obvious)that in most cases you can vary an AC load for a desired current by taking the source from a variac. This can be particularly effective when combined with a coarsely variable load.

    • I am not always as formal as Dr Elger, although my notebooks look a lot like his- the problem is that I have maybe 10 projects in different stags of interruption. Typically I have more than a notebook for each project- I actually have a binder where I keep, data sheets, instruction manuals, distribution CDs, larger schematics etc. I also use notebooks that have 3 ring holes pre-punched or I found some plastic magazine holder "thingies" (at Staples) that allow you to put a magazine in a 3 ring binder- it works for thicker notebooks as well.

    • Max Back in the days of Microcontroller Central when tablets were just coming into their own, I did a blog called "Designer's Documentation App Needed" appealing for an app that I could use to replace my notebook. Looking at my records, it was published in mid 2012- in mid 2015, there still does not appear to be a single integrated app that could replace it. How about it someone? An app called "Logbook", or will I have to create it myself as a retirement project? P.S. Let me know if you want to reprise the blog.

    • Crusty Thank again. In the first part of this blog, I referred to a TI article "Combine power feed and data link via cable for remote peripherals". It confirms what you say- seems that backup cameras for cars also work on the same principle, despite being quite close to a local power source..

    • Max "My wife, Gina the Gorgeous, is a realtor. A few weeks ago she met a couple looking for a house. It turns out that the guy (we'll call him Mike, because that's his name) builds model railways. Mike wants to add lights to his model buildings, and he wants to include effects like having the lights come on and off in sequence and so forth, but he has no experience with things like microcontrollers and tri-colored LEDs." I can't help but wonder how the conversation moved from wants/ needs in a house to LEDs for a model railroad.

    • Crusty "the slave simply switches different values of resistance onto the power line to indicate fault, alarm and other states." Were the states mutually exclusive, or was the detector capable of decoding the more complex current of two faults combined?

    • Crusty Thanks for the kind words. I am interested to see that the " two wire voltage modulation from the master and current shunt return from the slaves technique" had such wide appeal. I was only reminded of it when I did the research for the article, and even then it was only from the design idea. Funny, I did quite a bit of work with fire control panels (mainly diesel engine controllers for the water pumps), and I never came across the technique. Most of technology in South Africa came from Britain, so I would have thought it would have shown up somewhere, even if it was a wheel re-invention.

    • David Thanks for the kind words. "You can remote a temp sensor from your electronics and still get 0.5 degree accuracy without worrying about the length of your wires." I thought I should point out a design idea from my colleague Girish Choudankar "Standard Bus Buffer Easily Extends 1-Wire Signal Off Board" here (http://electronicdesign.com/communications/standard-bus-buffer-easily-extends-1-wire-signal-board)

    • Max I have had a very similar experience with the PSOC 5LP. My design had the two SARs running simultaneously (I thought) at 1MSPS each feeding a DMA channel with a 3rd DMA channel accessing an external 8 bit number. The DACs were externally triggered and my application has the ability to change that sample rate. t was a fairly complex development (the only surviving blog of my journey is described here http://www.planetanalog.com/author.asp?section_id=3140&doc_id=561592) with many possible combinations and testing was quite convoluted, so only towards the end did I discover that the fastest sample rate behaved identically to the second fastest (half the rate). First problem was that in PSoC Creator 3.1 SP1 (the development interface) where the ADC worked on an internal clock (internal to the UI component) it simply limited the conversion rate to 700KSPS. The information did appear in the configuration block, but who knew to look? Anyway after much backwards and forwards with tech support we managed to configure it with an external clock (created in timer UI blocks, still part of the PSoC) to run at 1MSPS (version SP2 does not have the problem), but I still could not get the throughput because of course there is some processing and as anonymous said "No one has put features in their device for getting that data rate off of their device. " I also concur with anonymous' positive remarks about the PSoC, but then anyone who has followed my blogs and remarks (Hi Mom!) knows I am a PSoC aficionado.

    • David "I'd guess someone would still make them in one form or another. " I started poking around. I discovered Digikey doesn't uniquely recognize the word "germanium" and returns Schottky diodes. I did discover at least one- the 1N34A http://www.centralsemi.com/PDFs/products/1N34A.PDF

    • Max "There's all sorts of things around. Cypress Semiconductor have a graphical interface for their PSoC devices. You've played with the GPAK stuff from Silego so you know about their graphical interface (admittedly their chips are small in capacity)." I have worked extensively with the Cypress PSoC, and yes that is the approach that I was getting at. "Altium supports VHDL and Verilog, but they also allow you to create schematics of TTL-type functions... and so it goes... " The longer I work with Altium the more it irritates me, and I haven't even got near their VHDL/Verilog. What I was asking is: have Xilinx/Altera/Lattice etc. all moved away from the graphical approach altogether?

    • David "So germanium diodes (which start conducting at around 200 mV) are ideal for protecting sensitive meters but make sure the FSD voltage is less than 200mV! Put a couple of diodes back to back across the meter, and it will not get more than about a 50% overload, which it should cope with. Germanium diodes may leak slightly, which will have the effect of shunting the meter, so make sure your calibration is still correct." Maybe germanium diodes today are more robust than they were back in the 70s. I was working with the OA91 and they would burn out at the slightest excuse. I can't believe they could be used to protect anything! Can you still get germanium diodes, or are you taking them out of your surplus box?

    • Max "a lot of my friends are highly experienced embedded design engineers, but many of them come from a microcontroller (MCU) background" Actually my training pre-dated micros and so I think in terms of logic gates, flip-flops and shift registers, so I have no problem in understanding your expertly explained issues with software vs FPGA implementation. "Similarly, MCU-based designers have typically heard about hardware description languages (HDLs) like Verilog and VHDL; they understand that hardware design engineers use these languages to capture the design intent;" Actually I did some work on CPLDs eons ago using MAX Plus II. One option was to represent the circuit graphically and in fact there were TTL equivalent blocks that you could plonk down and wire up using schematic capture. You could create a custom function in AHDL (Altera's HDL, like VHDL I have bee told), but it was represented as a symbol that could be brought into the schematic capture. Given the complexity of the FPGA and the complexity of the functions that are being captured, does this graphical approach still exist?

    • To emulate the SAMTLSFABRIKEN equipment you could re-purpose your comptometer. Looks sort of familiar. And I will swear that the little wheel at the top right hand side looks just like a typewriter ribbon spool.

    • Max "A lot of my friends are highly experienced embedded design engineers, but they come from a microcontroller (MCU) background, so they often have only a vague idea as to what an FPGA is and what it does." I guess I would fall into this category. Given that I am late to the party, let me ask this: it seems to me that the design of FPGAs today is at least one level of abstraction above your discussions of LUTs and Muxes and that every is programmed in either Verilog or VHDL. How much of the detail do we really need to understand? Can we just get by, by writing the code and seeing what comes out the other side?

    • David "Available in a range from 1Ω to 1mΩ, these PCB- and heatsink-mountable resistors are made by Rhopoint and will dissipate up to 10W. Intended for precision current sensing, they are high precision resistors (1%) but would make great meter shunts. " Another company that makes a wide range of current shunts including some that look like the one in your photo is Isotek. http://www.isotekcorp.com/products/precision-and-power-resistors I haven't used them for a while and I am having some difficulty navigating around their website for general photos that I can say- "there, that's like your one", but take it from me, they do make great product range.

    • As a slight aside, here is an engineer's take on Stack Overflow, both as contributor and user http://www.embeddedrelated.com/showarticle/741.php

    • Hi Javi It's actually been a while since I actually wrote this. I never actually worked on a FSM, but I did ask on the course and there is an example provided although I am not sure if I found the right one. It does look as though you use look up tables to generate the FSM. I cannot see any option to create a text file like a VHDL in the user interface. Perhaps someone from Silego will correct me.

    • Elizabeth "but for the company I work for, a single source part from a company that doesn't own their own fab is a really hard sell" That would definitely put a crimp in my style.

    • I should also add: no latency on start up for peripheral configuration. There are probably a few other disadvantages of a micro compared to programmable logic.

    • Elizabeth I have looked at the ATtiny- this PWM design is a mental exercise. The product has long been superceded by a newer, more complex design. The ATtiny would have done- this is just another way and even smaller. The Greenpak does have the advantage that it is not a micro and unless you are using a state machine, you don't have to worry about glitches and watchdog timers etc. No software listings either.

    • Crusty You don't have to have Silego do the programming- you can do it yourself on the emulator. It's just that if you have a bunch to do it will be really finicky especially if you have age-compromised vision and fine motor control.

    • David Great article, as usual. I think you have omitted a very important part of the HMI. That is when you tap on the meter when you don't believe what you are seeing. On the odd occasion it has made a difference!

    • Ken Great article. I wish it had appeared 3 months ago- it might have helped me re-spinning a PCB. There is one device type you could have included though- the constant current diode (http://en.wikipedia.org/wiki/Constant-current_diode _ There is a good analysis here http://www.centralsemi.com/PDFs/other/ec051semiconductora.pdf An extension of the idea is the LM334 (http://www.ti.com/lit/ds/symlink/lm134.pdf )Adjustable current source.

    • Max "Another alternative is to vary the brightness of each of the sub-pixels. Now, LEDs can't be dimmed like traditional incandescent bulbs -- they can only be on or off (generally speaking). " I am not sure what you are trying to say here- LEDs can be dimmed adjusting the average current through them. You can vary the current by adjusting the resistor (unusual, but possible), adjusting the drive voltage by using a D/A converter for instance or by using the PWM technique which you describe in the column.

    • Max You did mention in your previous column that you were considering (at least theoretically) a single strip of 256 LEDs. Just looing at your conundrum, it seems to me that the single array would have been easier to manipulate. That being said, I expect you are not going to re-wire the hardware. I agree with you that there must be a way to create "strip[i].setPixelColor(row,R,G,B)" My programming technique is to poke around looking for a suitable example, so I am not much use (my wife could have told you that). There surely must be someone on embedded.com who knows C well enough to solve the problem of the declaration/intialization of an array of arrays. Perhaps a structure would work?

    • Max Looking good! The display is controlled a column at a time in the video- would there be a control that would allow you to turn all the LEDs on at once (hopefully without putting the power supply into overload)? More than slightly off topic- I see a wash stand to the right of the display. Would it be correct to assume that you have electricity, but no running water at home?

    • Have you come across the new twist on EE Times- you click on the comment link on the top right hand side where all the comments appear and it takes you to the comment, as desired. Then an advert pops up- if you click the X to cancel it, you are left at the blog itself, just as on embedded.ocm. Sigh!

    • WE always believed (not necessarily incorrectly according to the etymology section on Wikipeda (http://en.wikipedia.org/wiki/Budgerigar)) that the word "Budgerigar" is derived from an aboriginal (is that PC?) word meaning "tasty morsel".

    • I should add- it normally came after someone recited the old saw- "nothing succeeds like success".

    • ""Nothing succeeds like a budgie without teeth" is a real saying? Are you sure? Who on earth says that? What occasion would prompt one to drop this into the conversation?" It would be added as a non-sequitur when discussing some success or another. According to the internet it has British origins, so we came by it honestly.

    • "Nothing sucks like an Electrolux" was originally an advert for the brand. I remember it in South Africa where the word "sucks" didn't(at the time) have the same north american connotations.

    • Max This seems to be a can of worms waiting to be opened or as Oliver Hardy might have said: "another fine mess we are going to get into". On a lighter note, the talk of "sucks" reminded me of the saying: "Nothing succeeds like a budgie without teeth". I googled it and was astounded at quite how many sites just didn't get it.

    • Crusty I do have several more stories of the "exotic", most of which (like this one) were published on MCC, but now lost- I will probably resurrect them over time. However none of them were ever life threatening, like yours. Seems the mundane (as opposed to exotic) has much more adrenalin associated with it. Glad you made it to be able to share this and your other stories and knowledge with us.

    • david " I think Aubrey's will top mine - both technically and for exotic dangers...." I don't know- I am certainly envious of your time in the near-Antarctic on Marion Island

    • This looks like a really good idea. Since I am getting the feeling that there is an Arduino in my future, it would seem to me that this would be a "must have" since I am a great believer in emulating and simulating especially when the device being controlled doesn't take kindly to errors in signals. Guido's description of his talk really does sound inviting. Wish I could be there.

    • Max "One big problem for most of us is that that we don't have the time, energy, or knowledge to create apps for smartphones and tablets. Well, fear not, because we don't have to. One really cunning aspect to all of this is that, when using the Simblee development environment, anyone can now create apps for use on iOS devices (iPhone, iPad) or Android-based products without having to use Xcode or the Android SDK, and without having to get their apps into the iTunes or Google Play stores." You are not kidding- having worked on a rather complex project on Android, I second that. The problem is (or maybe was) that I now would like to create a few projects for test equipment with a tablet user interface. This may be the answer, especially since the Simblee has some I/O even without the shields. My question is, does one have to start with basic Arduinos before moving into the Simblee?

    • More derring-do for you, Max. Installation for some of the sensing stations involved avoiding crocodiles when doing the installation and testing.

    • The cyclone was supposed to be a once in 200 year event. Surprise, surprise, when 2 tears later another cyclone hit and washed away the sensing stations again. At that point I was only supplying the software, but my friend made quite a it money building the same system 3 time.

    • David Lightning in Southern Africa is always a problem. I remember working on a fire protection (sprinkler) system in a aircraft hangar. If it started sprinkling (rather corrosive chemicals) and the aircraft engines were exposed, the engines would be write-offs. As a result we used a rather sophisticated lightning detector(you can now get a chip to do t) and whenever there was lightning in the area our system ws disabled.

    • Max This story has a familiar ring to it. I do hope your outcome is better than mine. D nt base any conclusions on what you heard on the answering machine. My ophthalmologist's answering machine says she is only interested in Glaucoma, but she is happy to see my for all my complaints and eye tests. Let's hope this is something trivial.

    • Max I can partially identify with your concerns about the loss of an arm. Many years ago now, I had a pinched nerve in my neck with a resultant loss of the use of my right arm. I am so right handed that I always joke that you could cut off my left arm and throw it away and I would probably never notice. After some Physio (Physical in the US) Therapy and Chiropractic treatment, I regained some strength but I decided to train myself to use my left for things like mouse use etc. It never worked out- my brain could just not handle it. It took surgery to restore the complete use of my right arm. So I still figure my left arm is dispensable although I am sure I would noice its absence, but my right arm...

    • I share the same sentiments as expressed by the others. I have a library full of data books going back to 1975 or so, and it seemd to me that I was the only person in the world with some of the remaining data that was being requested on different fora. I decided to scan every piece of data I had which I managed to do and then I looked for suitable repositories for the data. Not many locations exist. One place that did accept the data and makes mine and other the data available for free is www.datasheet.com

    • Quirky and the least favourite processor that I ever used was the Scenix SX18AC. Scenix became Ubicom who then licensed the chip to Parallax, if I remember. The device was pin and code compatible with the PIC 16C5XX series. The only peripheral it had was an 8 bit timer clocked at the same speed as the instructions executed which made some sense for interrupts (of which there was one). The RISC processor ran at 50MHz (and later 100MHz if memory serves) and the idea was that you could make any peripheral ("virtual peripheral" was the terminology) in software because the execution speed was fast enough. I made a remove voltage monitor with a built-in 300 baud FSK modem (the analog parts had to be added on). I can't believe that I bought into the philosophy for a while.

    • Please forgive this product placement, but if you found this article interesting you will find similar ideas (I describe how to create a similar interface for the 8051) and much more in my book "Excel by Example: A Microsoft Excel Cookbook for Electronics Engineers" published by Elsevier/Newnes. -Aubrey Kagan