So lets start with the reason for this project...
I have a Fujitsu ICL PCTV that packs a FIC 486-GAC-V motherboard. The system is odd but interesting, with an integrated Cirrus Logic CL-GD5428-80Qc-A graphics chip, and 1Mb of dedicated memory.
Next to it are 2 expansion sockets in 40 pin ZIP format, that allows for a total of 2Mb (adding a couple of 256Kb x 16bit chips on top of the other 2 already onboard).
I've searched online but I didn't like the prices of the 40 pin ZIP modules I've found, too expensive for what it was, with no alternatives, and I needed 2 of them...
Then I decided to look into the datasheet of the chips, model HM514260ZP-8, and since there are 3 different packages for them, I designed a PCB that converts both the 40 pin SOJ and the 40/44 pin TSOP, into the 40 pin ZIP.
Already made 10 units, tested them for several hours each pair, and the thing simply works as I was expecting. Only used the 40 pin SOJ version since it is the only I have, but should work fine with the TSOP package. I added pads for soldering both options on the PCB.
I will make a few changes on the PCB itself (one change is adding pads for SMD capacitors for better stability), and then I will share the PCB design somewhere if anyone wants to make modules for itself.
I will also have a few pairs available for sale.