Wecome To The New Home Of TheEPROM9

CASIO RP-8 RAM Pack

KiCAD Files

As I don't really have any pictures other than of the machine I used to figure out the pin out, I am just going to link to the GitHub here: https://github.com/TheEPROM9/CASIO-RP-8

The other CASIO SF-3000 will be covered in it's own section as it does not work for one & no one else has taken internal shots & put them up online.

The schematic was a challenge to put together one having a CASIO RP-8 RAM card, however that did not stop me. I found this guys website that took one apart so I could at least see inside: https://manib.bplaced.net/blog/?page_id=209

I used his images for reference while getting the actual pin out from the SF-3000, only five pins did not connect to the internal RAM chip, by then it was child's play to figure out which pin went where.

I did not know the value of the cap so went for a generic 10uF, often used a filter caps.

The PCB layout was not to hard. The main thing I decided to do was make the board screw into the holder. That way I would not have to go all out making a custom 3D printed case.

Reverse Engineering

Using the SF-3000 allowed me to also test the dimensions of the RAM pack so I knew it would fin in the machine before the PCB was ever built. It allows allowed me to work out not only the dimensions of the pins but also where they needed to sit in relation on the PCB so they would meet correctly when installed in a computer.

I was also able to verify my design later as I found the service manual for a CASIO FX-850P which contained a schematic for a RP-33 RAM pack here: https://archive.org/details/casio-fx-850-p-service-manual/page/n15/mode/2up

The other place I was able to verify my design was here: https://www.pisi.com.pl/piotr433/fx870_he.htm

This guys website is one of the only ones out there that contains a ton of technical information on these CASIO computers. They have gone to quite some reverse engineering lengths to pull the data they have. They have to pin out for the RAM card from the computer side, once again for an RP-33 RAM pack.

So sometimes when reverse engineering stuff you have to look at alternate sources for your information.

Page updated

Google Sites

Report abuse