Hi all
what are basic differences between the 8051 family and the 80251 family ?
Are they close family relatives?
Thanks Eliahu
Basic difference is that the difference is big.
Exactly why do you ask?
the 251 (Intels pitiful attempt to make a "16 bit '51") is dead. Atmel, I guess, still makes it, but it is definitely EOL.
basically, today, 16 bits is dead, you have 8 or 32.
Erik
a "pitiful attempt" due to a desperate desire to keep it "binary compatible". The other "16 bit '51s (Siemens and Philips) were much better designed, but, alas, these are also EOL or close.
Just as the Z80 extended the 8080 processor, a 251 processor got extra instructions by use of an extension byte.
But the main advantage was that it consumed much less clock cycles/instruction. But you don't need a 80251 for that - many newer 8051 chips works with way less than the 12-cycle concept of the original 8051. And at way higher clock frequencies too. And there are 8051 chips supporting more than 64kB of code space.
Many thanks Eliahu