BigDumbDinosaur wrote:
And then there's this statement, which appears to have been lifted verbatim from another site that was also more errors than useful information:
The 6502 instruction-set also included a set of binary coded decimal (BCD) instructions under the "Decimal Mode" of the 6502 processor.
Or, how about:
In addition, the 6502 processor introduces the idea of "zero page" which improves the speed of communication.
That would be news to those who designed the MC6800. And, of course, zero page (direct page with the 6800 and the 65C816) addressing has nothing to do with communication.
I see these as part of a language problem. ADC and SBC behave different under decimal mode. So one could actually see them as a different set of instructions - switched to by decimal mode. Zeropage instructions indeed improve the speed of communication with memory, they take less cycles to execute and that means more bytes/second to/from RAM. The wording is incorrect, the meanig is right. OK, it wasn't the first CPU to have zeropage instructions.
I have googled the wording in the decimal statement and yes, it shows up on another site... of the same guy.
And by the way, he does know about the 65c02, as he lists it here:
http://www.6502.buss.hk/glossary/8-bit-cpuI don´t understand, why it is so hard to say " I am not interested in ancient 6502 stuff, I have moved on" and leave sites like these to their intended audience. Its a low level introduction to 6502 assembly, nothing more and nothing less. I didn't spot any errors on the site pertaining to this subject, neither did I see any related errors mentioned in this thread.