jimc@druks.ATT.COM (CochraneJ) (06/03/89)
I'm looking for a reliable method to expand the memory of my 1040 ST to 2.5 megs. I would appreciate recommendations of expansion methods that are available (especially from first hand experience) which are reliable and will not get in the way of future (reasonable) modifications and additions (such as adding an 68000 accelerator board or PC-Ditto II). I would also appreciate any warnings of methods to avoid and why. I'm not a hardware expert at all, but I would be willing to pay a good repairperson to do it if the expansion involved much soldering. I'm also interested in hearing about pricing, of course, although reliability is the most important consideration. Since this information would probably be useful to other ST users here, it would probably be best to post to the net rather than sending me mail. Thanks for any suggestions, advice, horror stories, etc. Jim Cochrane
chad@norge.dec.com (06/29/89)
Hi I would like to know if replacing one row of 256kb chips (16 chips) with one row of 1 megabit chips in a 1040 or 520STFM/upgraded will give the magic 2.5 meg RAM on the motherboard. Is there a problem with this? Also, I would like to DIY upgradethe old style 520 to 1 meg using any method not requiring an add on board. That means most likely piggybacking. Could someone please post what needs to be done to do this. Ie, any extra parts needed, any pins not to solder, any jumpers, etc... Thanks Chad
hcj@lzaz.ATT.COM (HC Johnson) (06/29/89)
In article <1280@hiatus.dec.com>, chad@norge.dec.com writes: > > Hi > > I would like to know if replacing one row of 256kb chips (16 chips) > with one row of 1 megabit chips in a 1040 or 520STFM/upgraded will > give the magic 2.5 meg RAM on the motherboard. Is there a problem > with this? > > Also, I would like to DIY upgradethe old style 520 to 1 meg using > any method not requiring an add on board. That means most likely > piggybacking. Could someone please post what needs to be done to > do this. Ie, any extra parts needed, any pins not to solder, any jumpers, etc... 1. 1 meg drams are narrow, 256k drams are wider. there may also be a differ- ence in pinouts. my ezram-II uses 3 (thats three) plug in strips for each ram position--wide for 256, narrow for 1 meg. 2. my second atari is a 520ST with a 1 meg upgrade. each chip has piggybacked on it a second 25k dram. All pina are soldered except for the chip select. It works, and there are no connectors to work loose like my ezram. Howard C. Johnson ATT Bell Labs att!lzaz!hcj hcj@lzaz.att.com
lharris@gpu.utcs.utoronto.ca (Leonard Harris) (06/30/89)
In article <664@lzaz.ATT.COM> hcj@lzaz.ATT.COM (HC Johnson) writes: >In article <1280@hiatus.dec.com>, chad@norge.dec.com writes: >> >> Hi >> >> I would like to know if replacing one row of 256kb chips (16 chips) >> with one row of 1 megabit chips in a 1040 or 520STFM/upgraded will >> give the magic 2.5 meg RAM on the motherboard. Is there a problem >> with this? >> >> Also, I would like to DIY upgradethe old style 520 to 1 meg using >> any method not requiring an add on board. That means most likely >> piggybacking. Could someone please post what needs to be done to >> do this. Ie, any extra parts needed, any pins not to solder, any jumpers, etc... > >1. 1 meg drams are narrow, 256k drams are wider. there may also be a differ- >ence in pinouts. my ezram-II uses 3 (thats three) plug in strips for >each ram position--wide for 256, narrow for 1 meg. > >2. my second atari is a 520ST with a 1 meg upgrade. each chip has piggybacked >on it a second 25k dram. All pina are soldered except for the chip select. >It works, and there are no connectors to work loose like my ezram. > >Howard C. Johnson >ATT Bell Labs >att!lzaz!hcj >hcj@lzaz.att.com What? 1 Meg rams are 18 pin devices - 256K rams are 16 pin devices They are both packaged on 0.300 inch wide spacings. /leonard .]
clf3678@ultb.UUCP (C.L. Freemesser) (07/01/89)
In article <1280@hiatus.dec.com> chad@norge.dec.com writes: > >Hi > >I would like to know if replacing one row of 256kb chips (16 chips) >with one row of 1 megabit chips in a 1040 or 520STFM/upgraded will >give the magic 2.5 meg RAM on the motherboard. Is there a problem >with this? > (Rest deleted) Since the 4 meg upgrade boards sell quite well, it's a bit obvious that what you want to do cannot be done. Actually, the 256k chips have a different pin signals than the 1 meg chips. I think they might actually have more pins (the 1 meg chips, that is), but am not sure. I have an old 520 with the original EZ-Ram board in it. I do NOT suggest piggy-backing. Too messy, hard to remove if you need your computer serviced, etc. Chris Freemesser, Rochester Institute of Technology | What I like : BITNET: %clf3678@RITVAX | 1) My Atari ST USENET: Just reply and hope it gets through | 2) My '77 Mercury "Another brilliant mind ruined by higher education" | 3) Coke Classic
cbz@cbnewsm.ATT.COM (craig.b.ziemer) (08/14/89)
I recently posted a request for info on the EZRAM II RAM upgrade board and received no replies. So, let me rephrase the question. Can anyone send me any information (opinions, etc.) on ANY RAM (1M) upgrade boards available? I'd like to checkout this possibility before I try the DIY piggyback-type upgrade. Suggestions appreciated! * Craig B. Ziemer %% DISCLAIMER: AT&T does not * * AT&T Bell Laboratories %%%%%% officially support what I * * Reading, PA %% just said, in fact, they * * UUCP ADDRESS: alux6!cbz %% rarely do :^) *