19 May
1998
19 May
'98
12:44 a.m.
Digging thru the VAX 780 manuals...
They have here some crud on how the microcode works. Where it starts and ends,
field definitions, etc.
I know basically how microcode works. It's the one-cycle instructions like
"gate data bus to address bus" or "gate data bus to ALU".
One MOV can be 2-5 microinstructions.
The large question I have is: How does the MOV translate to microcode?
Does the VAX figure a microcode offset based on the opcode? Is there a table
of entry points somewhere? How is this done?
Another thing, the VAX 780 was microcoded from the console RX01. Does anyone
have a copy of that RX01? Can anyone get a disk image? What else was on there?
(RT-11? P/OS?)
Just being annoying...
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