Sinclair ZX80 / ZX81 / Z88 Forums

Well no good news I'm afraid. I replaced the RAM and no change, it still won't start up...

Oooh, upgrades! Must have!
Will they be going up on the store? I,ve probably missed it, but is there any details on the upgrade?

-John-

Are you well practised in desoldering? There are a couple of best practises I can suggest if you're not used to this kind of thing. C Thanks, any suggestions would be greatly appreciated! I've done some, so I've got desolder tape and an iron with a suction tip. I usually use a clipper to cut the le...

I was digging out some my old equipment from the attic at my parents place... which is a retro computer fest in and of itself, as I'd forgotten a lot of the stuff I picked at flea markets 15-20 years ago... when I ran across something I'd forgotten about.. I can't remember if this was and eBay purch...

Ok the RAM's on the way! Beyond grounding, any suggestion about things I should try will when/while I have the old RAM cut out, and far as soldering what do you guys thing is safer 15, 25, or 35 watts?

-John-

I can't help with tape but I know a little bit about zxpand :lol: What language are you going to be using? BASIC is almost out of the question as it has no native input/output calls. You will need to program in C, machine code or call machine code routines from a BASIC program. Lol. Yes, I can see ...

Sure thing - Rich can give you the actual mouser (digikey?) product code, but they're a standard 32k x 8 static ram in a 0.3" package. Thanks :D If I've read it correctly, what I'm look at is a Cypress Semiconductor CY7C199CN-15PXC, which I can get at Newark/Element14 ( 19M3763 ) or Digikey ( 428-2...

Does any know of, or can point me in the direction of to, I/O routines that I can call from BASIC to read data/files from tape and, in particular, from a ZXpander?

Thanks!
-J. E. Bielak-

Of course the other option is for me to desolder the RAM and drop another in... just give me the specs, and if they're the ones I think, the chips are fairly cheap so I can pickup some thing like a dozen for the cost of a good lunch

-John-

So to sum up, you have swapped individually each socketed chip, and each time you tried both ZXpands the old one failed to work, but the new one worked okay. And you have swapped all the socketed chips over, and again when you tried both ZXpands the old one failed to work, but the new one worked ok...