This is a long shot, but...
I am going to replace some components on my Ace 1200 to tr to get the normal hardwired Slot 6 drives to work again. I sspect the r/w/ motor control at H12, but if it should end up being H10, the 'Franklin FDC' gate array ASIC (this combines several aspects of the Disk ][ card onto an ASIC, then I have two options.
1. Find another Fanklin FDC chip. I am open to this, if anyone has spares. This was used on the Ace 1200 and on some Franklin Slot 6 Disk ][ clone cards.
2. Map out what the ASIC does, and use off the shelf components on a PDB with a header to plug into the FDC chip socket to make it work.
I do not know what to do if it falls on the latter. Franklin had excellent schematics of their PCBs, but not their ASICs. If anyone has anything that'd be of use, please LMK.
THis system, NOS as it is, is a doorstop unless I can get it to work off of normal Slot/Jumper 6 disk drives. No CP/M, and a lot of normal software won;t run, because it all expects Slot/Jumper 6.
My pther option, is to cut out all f the cstom FDD logic and make slot 6 work normally, but this seems an absolute last-resort, and I would sooner do it on another 1200 board, than demolish a NOS board to do it.
If anyone has parts that can help, or knowledge that can help, please LMK. I am never selling this system, even if it becomes a paperweight. It is one of the best hybrid systems available, especialy given the excellent CP/M support built into it.