The Serial Bit Rate Converter runs an ARM7 CPU which is complete overkill for the simple job of relaying serial data. I’ve often thought I should redesign it to run a cheaper and less powerful CPU like a PIC or AVR. I originally designed it with an ARM7 simply because I like them and enjoy programming them.
Another reason I never redesigned it for AVR is that the economics are not that great. It would probably take $5 off the price but cost me a couple of weeks of time to redesign the entire thing.
This decision has had an unexpected benefit recently. A customer asked me if I could add an extra function to search-and-replace byte sequences in the data stream. Now I’m really glad to have 50 MIPS on board because a smaller CPU might not have had the grunt to do the job.
So having a way-too-powerful CPU has produced a long-term benefit to enable me to quickly sieze a market opportunity.