Various studies peg the entire embedded tool market at around $3 billion, a number I just don't believe. Often analysts inscrutably lump RTOS sales in their tool figures, which makes little sense. But summing up sales of the biggest players in the industry, with RTOSes and all, gives a number of well under $1 billion. So $1.25 billion in oscilloscope sales overwhelms the entire size of the embedded tool market. One would think a large percentage of those scope sales would be to us, the embedded hardware and software designers.

This industry went through a radical tools transformation over the last 15 years. In the 1980s and '90s, most of us used in-circuit emulators (ICEs). These tools let us debug in the procedural domain--single step, examine variables, and so forth--as well as the time domain. The ICE supported the latter via real-time trace, performance analysis, timers, and other features that are essential to managing microseconds.

But processor speeds increased to rates that made it impractical to bring signals to an ICE pod. Surface mount technology shrank packages to sizes that couldn't be probed. And sophisticated on-chip features like caches, pipelines, and MMUs removed any correlation between what the CPU was doing and the signals on the pins. The ICE market all but disappeared, though a few companies, for instance Lauterbach and Signum, continue to provide such tools.

BDM and JTAG debuggers replaced the ICE in most development shops. Cheap and easy to set up, these devices used logic on the target CPU to move debugging data to a PC. They worked regardless of target clock rate and used a simple dedicated connector, which ameliorated all of the surface mount issues.

But BDM and JTAG debuggers provided nothing for handling the time domain. The gave us a Visual Studio-like interface. Scopes therefore became much more important. Twiddle a bit in the code and the scope will instantly show execution time, latency, and pretty much anything else you need to see.

The good news is that the BDM/JTAG tools have improved. More vendors are throwing transistors at the debugging problem and add all sorts of wonderful on-chip resources like hardware breakpoints, trace, and more. Real-time debugging returned.