hcj@lzaz.ATT.COM (HC Johnson) (07/17/89)
>From Xerox.COM!"Paul_Millard.WGCERX" Paul writes:
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2. my second atari is a 520ST with a 1 meg upgrade. each chip has
piggybacked on it a second 25k dram. All pins are soldered except for the
chip select. It works, and there are no connectors to work loose like my
ezram.
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Is The above correct, can i piggyback 256k bit drams to make my 1040 2mb?
Send me info (An idiots guide as i would'nt like to muck my ST up!!) on how
to do the upgrade.
Cheers Paul.
P.s My 1040stfm is really an upgraded 520stfm.
Sorry, Paul, you cannot get to 2 meg that way.
The Atari only supports 2 banks of memory - which may be sized 256K or 1 MEG
(size = 2 meg is allowed, if you get 2 meg drams ??? ).
The 520ST upgrade I referred to is actuall adding a second bank. Only most
of the pins are soldered to the first bank because the lines are common.
Howard C. Johnson
ATT Bell Labs
att!lzaz!hcj
hcj@lzaz.att.comacs60222@zach.fit.edu ( ENRIQUEZ) (07/22/89)
>From Xerox.COM!"Paul_Millard.WGCERX" Paul writes: > >************************************************************** >2. my second atari is a 520ST with a 1 meg upgrade. each chip has >piggybacked on it a second 25k dram. All pins are soldered except for the >chip select. It works, and there are no connectors to work loose like my >ezram. >************************************************************** Having (finally) decided to upgrade to 1M, all that remains for me to do is pick the method in which to do this. The above mentioned solution seems promising (i.e. inexpensive) and I would like, if possible, a more detailed description of the process of piggybacking(?) the drams. Since I am no expert (but learning :-) on this sort of thing, perhaps one kind soul could mail me either a reference or "walk-through" instructions on the installation of the drams. thanks mark enriquez acs60222@zach.UUCP