🚀 go-pugleaf

In article <1992Nov18.102423.4349@odin.diku.dk>, torbenm@diku.dk (Torben AEgidius Mogensen) writes:

|> Don't expect the memory to be able to run faster even if it is newer,
|> it will always be cheaper to use slow RAM. As for changing the

I've yet to come across a RAM upgrade with memory slower than 80ns..  compared
to the 120ns stuff in your 310, that's a big improvement, and should run
fine on a 12Mhz bus.

|> crystal, the apparent conclusion to the discussion on this group is
|> that it can't be done, as the same clock feeds the IOC etc. Making IOC
|> run faster will make the timing of i/o go wrong. The new machines that
|> use 12MHz memory still use a 8MHz IOC, and some advanced circuitry to
|> interface these. It would be very difficult (if possible at all) to

The advanced circuitry you refer to consists of a couple of PALs which
divide the clock and synchronise bus cycles.

You can certainly speed the bus up on a 400, so I suspect it's possible
on a 300.  Doing so involves a lot of butchery (including cutting tracks,
wire links etc) and some experience with PALs.  If I can get the
disclaimers right, I might post the details (though I plan to try it out
on a /1 and a 300 series first for the sake of completeness).

Cheers

Bob

-- 
  Robert J. Voisey  :  r_voisey@csd.uwe.ac.uk
         -- Probug Software Developments --
162 Staplehill Rd, Fishponds, Bristol, Avon, England