aglew@ccvaxa.UUCP (07/31/86)
>Hmmm. It just occurred to me that the speed of main memory is a big >factor in the opcode/microcode trade-off. Could Vaxen have been designed >with much slower main memory in mind? (Or faster cache?) > Ronald O. Christian (Fujitsu America Inc., San Jose, Calif.) > seismo!amdahl!fai!ronc -or- ihnp4!pesnta!fai!ronc The cost (both in dollars and in space) of memory also plays a factor. I have a card (an old punch card - I scrounged several boxes when the site I was working at finally threw out the keypunches) on my wall with this on it: WOW! In the early 1970s, 8K of ROM = 8 bits of register. What a reason for microcode! [from one of Patterson's papers] I'm waiting for this to happen again, probably in the early days of optical computers. Of course, you can always execute microcode from RAM... Andy "Krazy" Glew. Gould CSD-Urbana. USEnet: ihnp4!uiucdcs!ccvaxa!aglew 1101 E. University, Urbana, IL 61801 ARPAnet: aglew@gswd-vms