I 've officially dubbed the time between Embedded World (first week of March in Nuremberg, Germany) and the Embedded Systems Conference (last week of April, San Jose, CA) as Embedded Season. These are the two largest trade shows in the embedded sector, and it's the time when vendors in this space roll out their most significant products of the year. This year, the activity is at an all-time high, especially in the microcontroller industry.
The weeks prior to Embedded World were filled with briefings from vendors announcing MCUs that were either super low-power or extremely low cost, or both. Many of these aren't going public until the Embedded Systems Conference, so I'll have to do a follow up column with all the details. Suffice to say that if you're a designer looking for a low-power or low-cost MCU, your prayers have been answered.
In more than one conversation, the question came up, “Does your 16- or 32-bit MCU make 8-bit devices obsolete?” While none of the vendors would go on record as saying yes, it was obvious that that was their intention. With prices for these devices hitting extremely low levels (like $0.25 in one example), it's hard to justify going with an 8-bit device when you can get the performance of a 16- or 32-bit MCU.
The biggest reason I've found for designers to stick with an existing architecture, even though it may not be the best choice for their design, is simply familiarity with the architecture. And that's perfectly understandable. Why would I want to invest in learning a new architecture, when I barely have time to get my design out the door using an MCU that I'm familiar and comfortable with? Assuming the existing architecture is good enough, it may not pay to switch.
The “specmanship” battle on the power front is reaching a crescendo. I met with three different MCU vendors in one week who all claimed that their device was the lowest power, and in each case, by a significant margin. Unfortunately, because of how each vendor presented its case, each was correct. It just depends on how you measure the power. It could be measured in full-on mode, in sleep mode, or in one of many low-power modes. It could be measured at 3.0 V, or it can be measured at 1.8 V. Or it can be measured over a time period using the wake-up time as the key characteristic (the faster you wake up and make your measurement, the faster you can go to sleep).
In each case, it's up to the designer to do his due diligence, to choose the MCU that operates best in his specific application.
Will 8-bit devices become obsolete? I doubt it. But those vendors certainly have their work cut out for them.
Richard Nass is editorial director of Embedded Systems Design magazine and the Embedded Systems Conferences. In a past life, he was editor in chief of Portable Design magazine and was a technology editor with Electronic Design magazine. He has a BSEE degree from the New Jersey Institute of Technology. He can be reached at .