An Arduino Mega 2560 shield (HAT) to test Commodore PET MPS 6550 RAM chips.

 Modern EPROM programmers like the TL866 are unable to read obsolete MPS6550 RAM chips used in Commodore PET's.

The MPS6550 is a custom 1024 x 4 bit RAM chip manufactured by Commodore.

I built a shield for the Arduino Mega 2560 which runs 4 tests:

Writes B1111 to each memory address and verifies
Writes B0000 to each memory address and verified
Writes alternate B0101 and B1010 to address and verifies
Writes incremental data to each address and verifies

To use this shield you will need to have a Arduino Mega 2560 (Not included in sale) and have some knowledge using Arduino IDE to upload the code to the Arduino, and view the serial output results from the test.

I use this to also test the MPS6550 replacement RAM chips that I sell on my store. (https://www.ebay.co.uk/itm/256494824756)



For more instruction on using this shield see my github page. 

https://github.com/MyRetroStore/MPS6550-RAM-Tester


Arduino Mega 2560 and MPS6550 RAM Shown in the photos are not included in the sale. You will only receive the shield. 




Please contact me if you have any queries and I will be only too happy to answer them.

Please check out my other items for sale. 


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