exxos's Atari, Amiga & retro forum

I've seen a few dram tester projects around, I thought I would make my own.
I've not worked with dram before and I've been using a PIC16F628A to make a simple tester.
The bit which I've not found much information on is mapping the address to the RAS&CAS address.
If I use a TC514256A 256kx4 how would you map 0x10000 to the RAS&CAS address? I dont know if there a standard way of doing it?

My way of testing was to write 0000,1111,0101,1010 to each 4 bits, refresh and read them back and make sure they are the same. Then output on a serial connection if each address passed or not.

Regards

See my post here: https://www.exxosforum.co.uk/forum/viewt ... =10#p34010

Someone has built a DRAM tester, and I've linked to it, it may be of use to you.

Currently I have a few different motherboards which I used to test RAM in... But at some point I want to design some RAM adapter boards for the H4 where I can test out various DRAM chips just by changing the adapter board... It would reduce the amount of motherboards I have dotted about for testing the chips.

I have one board that's my test buck, with the first RAM chip socketed, but I also built a ZIF adapter that plugs in so I can use it for quick tests. Also considering putting a ZIF socket where all the chips are for quick testing of anything that isn't in a PLCC socket.