There are some NMOS versions of the 5101, i.e.2101 that are pin-compatible,
though they want to be operated at 5 volts, that might do so long as you're not
going to run it from a solar cell or a single AAA battery. These occasionally
pop up at Jameco, JDR, etc.
Dick
----- Original Message -----
From: "Tony Duell" <ard_at_p850ug1.demon.co.uk>
To: <classiccmp_at_classiccmp.org>
Sent: Wednesday, April 18, 2001 12:33 PM
Subject: Re: looking for some old RAM chips
> >
> > ok...i got my CDP-1802s so that i can build the COSMAC Elf...
> > now i just need the RAM that the schematics have....i believe that it is 2
> > 256x4 RAM chips...if anyone has these or can let me know where i can find
> > them could you please let me know
>
> If you're not trying to build an exact replica, but just something that
> will work, you could use a more modern SRAM, like a 6264 (8K*8). Such
> chips are cheap now. Just tie the unused high-order address lines on the
> RAM to ground, leaving 8 low-order ones to connect to the system address
> bus. The rest of the circuitry should be essentially unchanged.
>
> I've done this sort of thing several times when repairing older equipment.
>
> -tony
>
>
Received on Wed Apr 18 2001 - 18:34:17 BST