DRAM Tester for ZX Spectrum, C64, Oric, Jupiter Ace and other retro computers and equipment.

This DRAM tester supports 1 bit DRAM devices from 4Kbit to 256K bit (eg. MCM4096, M4027P, 4116, TMS4532NL3/4, M3723L/H, 4164, 4128, 41256, etc.).

1. Support for 4Kbit parts (e.g. M4027 & MCM4096)
2. Support for piggybacked DRAM such as Samsung KM4128 used in early PCs
3. Multicolour LED output to make the results simpler to read and more intuitive (e.g. working columns show as a horizontal bar, working rows as a vertical bar, fully working as a a square box)

It has a simple power requirement, needing just 5V and drawing less than 100mA, so it can be powered from any USB port with a standard micro-USB cable. The tester generates all of the required voltages (+3V3, +12V, +5V and -5V) from this single supply.

How to Use

1. Connect the board to a USB port to provide power
2. Put the DRAM chip in the correct socket: The left socket is for parts that require -5V on pin 1, +12V on pin8, +5V on pin 9 and 0V on pin 16 (e.g. MCM4096, M4027P, 4108 and 4116), all other types should ONLY be tested in the right socket.
3. Press the start button and wait for the result to show on the LEDs.

Please note that the LEDs will flicker while the DRAM is being tested, this is normal.

Example Results