Tony wrote...
Yes, modern SRAM is fast enough. But that's
'easy' in theory. Firstly you
have to have some way of switching the SRAM between the device and the
loader
Dual port SRAM is one answer. Or, I'm not sure what the power on test
in
Sure, but have you looked at the price :-)
microcode does on the MX's, but my guess is it
doesn't touch the add-on
microcode. The loader roms probably aren't touched either until called from
the front panel. If the RPL stuff is turned on, it may though. I think the
OK. I was thinking about the microcode ROMs in an HP9810 (somethign that
_I_ am working on, and those are most certainly 'hit' as soon as INIT is
deaseserted and the microocde program counter starts to change. I prefer
to think of general-purpose solutions (i.e. somethign that will replace
every 256*4 ROM), rather than soemthing that works only in specific
machines under specific circumstances.
-tony