Fri Apr 12 12:15:01 2002
Date: Fri, 12 Apr 2002 14:59:54 -0500 (CDT)
From: Daniel Seagraves <firstname.lastname@example.org>
Is the stuff in ubin/*.mcr microcode?
If so, what's the format?
Several sections, for instructions, dispatch-table memory, tag-table
memory, and a couple other sections I forget. I dug up my old
LOAD-MCR-FILE code the other day -- I want to do a little software
archeology and disassemble and annotate the microcode -- but it's at
home. No symbol tables, alas.
Third, the two load bands you guys have; Could they be used to cold-boot
a real machine from absolutely nothing? (say, a machine with zeroed disk
Once upon a time, that's what one did: put a load band and a microcode
band on a disk, flag them as "default" with a magic tool, and the boot
process would load them up and go. (In my first weeks as a microcoder,
I would often build microcodes that didn't work; in that case I had to
lug the disk brick to another lab where I could hook it to a handy CADR
and move the "default" flag to something that worked, then lug it back.)
I think that would still work, but the "modern" way was to first boot a
special microcode that would offer a menu of bands to boot, including
load bands, microcodes, and diagnostics. Or was it two-stage: initial
boot and self-test, which loaded the menu boot? Fuzzy memory.