[comp.sys.atari.st] help on upgrading Atari STFM to 2.5 Megs wanted

CHT510@SATURN.UKC.AC.UK (06/16/91)

Hi,
   wondered if anyone who has upgraded an Atari STFM with DRAM's could help
me. I was planning on putting an extra couple of MEG in over the summer
and wondered if it was just as simple as soldering 16 * 1 MEG chips in.
I know that the STE is incapable of recognising 2.5 Megs of memory without
the aid of 'simmfix'. Is the STFM similarly affected when upgraded with
DRAM's ?
   One last thing. how fast does the access time of the DRAM's have to be.
Is 120 ns fast enough or does it need 100ns/80ns ?

I would be grateful for any help.

--
adam whitham,Eliot College,UKC,Canterbury,Kent,CT2 7NS.UK.
CHT510@saturn.ukc.uk.ac

Roger.Sheppard@actrix.gen.nz (Roger Sheppard) (06/17/91)

In article <9106161314.AA15971@lilac.berkeley.edu> CHT510@SATURN.UKC.AC.UK writes:
> Hi,
>    wondered if anyone who has upgraded an Atari STFM with DRAM's could help
> me. I was planning on putting an extra couple of MEG in over the summer
> and wondered if it was just as simple as soldering 16 * 1 MEG chips in.
> I know that the STE is incapable of recognising 2.5 Megs of memory without
> the aid of 'simmfix'. Is the STFM similarly affected when upgraded with
> DRAM's ?
>    One last thing. how fast does the access time of the DRAM's have to be.
> Is 120 ns fast enough or does it need 100ns/80ns ?
> 
> I would be grateful for any help.
> 
> --
> adam whitham,Eliot College,UKC,Canterbury,Kent,CT2 7NS.UK.
> CHT510@saturn.ukc.uk.ac

There are no problems in using 2.5 megs on a STFM, also use SIMMS.
There is a file at atari archive 2_5ram.zoo, on how to do this, this is
by far the better method.

You don't need fast rams or simms 150ns or faster, have a look in
the UK Computer Shopper for simm prices, from what I remember about 30 pounds
for a one meg simms.]

I have just upgraded my STFM1040 to 2.5 Megs , but using simm sockets,
mounted on vero board, I had to remove the first bank of ram, but I
did provide the option to go to 4 megs..

The normal way to do it, is to just stick the simm cards down with
double sided tape, plus some wiring and also removing a bank of ram..
-- 
***  Roger W. Sheppard        *    Roger.Sheppard@bbs.actrix.gen.nz  ***
***  85 Donovan Rd          *  *   At least I don't Flicker, not     ***
***  Kapiti New Zealand..    *     like a dying light globe. !       ***