Some of the most popular vintage computers are now more than forty years old, and their memory just ain’t how it used to be. Identifying bad memory chips can quickly become a chore, so [Jan Beta] spent some time putting together a cheap DRAM tester out of spare parts.
This little tester can be used with 4164 and 41256 DRAM memory chips. 4164 DRAM was used in several popular home computers throughout the 1970s and 1980s, including the Apple ][ series, Commodore 64, ZX Spectrum and many more. Likewise, the 41256 was used in the Commodore Amiga. These computers are incredibly popular in the vintage computing community, and its not uncommon to find bad memory in any of them.
With an Arduino at its core, this DRAM tester uses the most basic of electronic components, and any modest tinkerer should have pretty much everything in stock. The original project can be found here, including the Arduino code. Just pop the suspect chip into the ZIF socket, hit the reset switch, and wait for the LED – green is good, and red means it’s toast.
It’s a great sanity check for when you’re neck deep in suspect DRAM. A failed test is a sure sign that the chip is bad, however the tester does occasionally report a false pass. Not every issue can be identified with such a simple tester, however it’s great at weeding out the chips that are definitely dead.
If you’re not short on cash, then the Chip Tester Pro may be more to your liking, however it’s hard to beat the simplicity and thriftiness of building your own simple tester from spare parts. If you’re a little more adventurous, this in-circuit debugger could come in handy.
9 thoughts on “Simple DRAM Tester Built With Spare Parts”
Thought this was about whiskey at first 🤣
Ditto. I was wondering if someone had figured out how to build an arduino based ‘nose’ that could tell the difference between Cardu, Glenrothes, Glen Ord, and Bell.
I didn’t know how badly I wanted an electronic nose until just now!
Congrats for improvements!
I feel honored seeing my DRAMARDUINO lives on and on! (https://forum.defence-force.org/viewtopic.php?t=1699)
Great! I feel honored to see my #DRAMARDUINO lives on and on! 🤘
It was (and still is) a valuable asset to the vintage computing community, well done :)
Perfect to weed out the utsource crap.
Nice project! I made my own DRAM tester when I found how much they want on eBay for pre-made testers.
I’ve always wondered why there isn’t a low cost DRAM tester. I made one with Arduino years ago using this guide. Recently I got TL866 II and it does test SRAM but it doesn’t test DRAM
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