2004 8051 unit sales 1953

There is more than one C compiler, or at least there has been in the past. Keil may be the only one still in business.

However, on this size of CPU not everyone uses a compiler. I've done quite a few 8051 controllers over the years, all in buttembly language. Compilers took too long and were too cumbersome. Resources are dear on this clbutt of machine; the compiler overhead can be of significant cost if it forces a move to the next larger memory size in a family. In many cases I had to control loop timing down to the tens of microseconds, not so easy using compiled code.

I've found that a library of solid, debugged buttembler language routines to be worth more than a compiler in terms of time saved in development. Now I'd never propose developing on an Alpha or x86 in buttembler, but low end embedded controllers are a whole different matter. Programs are oneshots, rarely maintained or updated. Whatever ships is the way it will be until the next production run, which often as not uses a completely different '51 variant. The economics are different than for the usual commercial IT type data processing. Component costs are of more concern than development costs. Jack Peachicken