ching@brahms.amd.com (Mike Ching) (11/10/90)
In article <9333@b11.ingr.com> lhughes@b11.ingr.com (Lawrence Hughes) writes: ... > >The Z80 WAS upward compatible with the 8080, at both architecture and binary >opcode level - curiously enough, though, the bright boys at Zilog invented >a better (read "different and incompatible") symbolic assembly langauge >which made it much more difficult to take advantage of the Z80's extended >instructions: you either stuck with Intel mnemonics (and the 8080 subset) or >worked with Zilog's "preverted" ones (e.g. almost half the actual binary >opcodes mapped onto the single symbolic opcode "LD"). Zilog's symbolic >language was SUCH a turkey, that several extended Intel symbolic assembly >languages were developed (and widely used) leading to a regular tower of Babel. >Clever, Zilog. > ... > >Larry (in shaky voice: "When I was a lad - we barely had 64K bytes of >memory, and were GRATEFUL for it".... cough cough) Hughes > Weren't the Zilog mnemonics a result of Intel copyrighting theirs? Ones already in use like CALL and PUSH could be used by Zilog but the "new" ones like MOV and ANA were copyrighted. Which leads to absurdities like Zilog putting a trademark on the letter Z. Mike Ching
dhesi%cirrusl@oliveb.ATC.olivetti.com (Rahul Dhesi) (11/13/90)
Zilog's symbolic language was SUCH a turkey, that several extended Intel symbolic assembly languages were developed... Zilog's assembly language was far more regular and elegant than that of Intel. The proof of the pudding is that Intel's later assembly languages (8086 onwards) far more resemble Zilog's language for the the Z80 than Intel's language for the 8080. Imitation being the sincerest form of flattery, etc, Intel essentially replaced Zilog's LD with MOV, and replaced Zilog's parentheses (denoting indirection) by sqare brackets. There were, however, many 8080 programmers who were unwilling to spend the 25 minutes it took to learn the new language and instead spent weeks and months inventing awkward extensions of the old one. -- Rahul Dhesi <dhesi%cirrusl@oliveb.ATC.olivetti.com> UUCP: oliveb!cirrusl!dhesi
dhesi%cirrusl@oliveb.ATC.olivetti.com (Rahul Dhesi) (11/13/90)
In <2682@cirrusl.UUCP> I wrote: Intel essentially replaced...Zilog's parentheses (denoting indirection) by sqare brackets. ^^^^^ The word rhymes with "scare" and denotes a type of symbol that causes 8080 programmers to flee in fear. :-) -- Rahul Dhesi <dhesi%cirrusl@oliveb.ATC.olivetti.com> UUCP: oliveb!cirrusl!dhesi