Hi Jan and Erik,

What about this is "unwritten?" I thought the standard SFRs were a fundamental tenet of the 51/52 definitions. Are you saying that there is a vendor selling µ-controllers, calling them 8051s or 8052s, but without the standard SFRs?

I remember several years ago Cypress tried something like that with one of the early 80x86 µ-processors. I think they put out something that was essentially an 80386-SX, but they just labeled it 80386 and either led or allowed people to think it was a full 80386-DX. (As I recall they did add some trivial functionality and tried to beat Intel to market. They seemed to think that by being first they could set the DX definition.) It wasn't long before consumers would explictely ask if a computer had a Cypress µ-processor, and decline to buy the ones that did.