While waiting to receive the printed circuit board for the MSX cartridge, I started working on making a compatible USB card for the AKAI S5000/S6000 samplers.
The reason is that I know someone who is developing a new version of AKSYS that works perfectly under Windows 10 & 11. It turns out that not all Akai S5/6000 machines were shipped with this card. That's a shame.
So I studied the card I own and looked into whether it might be possible to create a new version.
It turns out that it is.
On the one hand, a USB component compatible with the one on the original USB card still exists today. And on the other hand, I was able to retrieve the logic equations of the PAL chip that is on this card.
For now, these equations seem to be correct, since I was able to repair another original but faulty USB card using a GAL programmed with my equations. So I am hopeful that this will work, even though the decoding performed by the original PAL is quite unusual.
The card's schematic is also unusual. Without going into too much detail, some functions are implemented by first latching a kind of register — registers made out of resistors and capacitors.
In short, the read and write functions are not direct but require going through other operations first.
In any case, I have completed the schematic and then the PCB for this card :
So, I have no idea whether this new card will work or not. The only way is to test it and compare the signals with the original card if it doesn't work.
Next steps after the first tests....
