🚀 go-pugleaf

In article <54...@bu.edu.bu.edu> a...@cs.bu.edu (Al Thompson) writes:
>In article <10...@cbmvax.commodore.com> mks@cbmvax (Michael Sinz - CATS) writes:
>|In article <54...@bu.edu.bu.edu> a...@cs.bu.edu (Al Thompson) writes:
>[...]
>|>
>|>Time out!  The opcode is a number, the letters are a mnemonic device so
>|>the programmer can avoid remembering the number.  There is no necessary
>|>correlation between the number of letters in the mnemonic and the number
>|>it represents.
>|
>|Yes, however, due to memory limits, many of the assemblers were written
>|such that 3-bytes for the op-code with the 4th byte containing some data
>|on how to build that instruction.  It made the search/parse code really
>|simple.  (My PDP-11 assembler had that until Macro-11 came out and was
>|just tons better and needed a disk drive to work at reasonable rates)
>
>Sure, but that is an engineering decision.  But, there is no necessary
>correlation between the size of the mnemonic and the opcode.

I did not say that it was necessary.  I just said that one of the reasons
so many of the older machines had "Fixed-Length-Mnemonics" was due to the
way assemblers were designed, not due to the opcodes.

/----------------------------------------------------------------------\
|      /// Michael Sinz -- CATS/Amiga Software Engineer                |
|     ///  PHONE 215-431-9422  UUCP ( uunet | rutgers ) !cbmvax!mks    |
|    ///                                                               |
|\\\///          "I don't think so," said Ren'e Descartes.             |
| \XX/                    Just then, he vanished.                      |
\----------------------------------------------------------------------/