Fun, Fancy, Frustrating, Floppy Drives - A4000D - Amiga 4000D

[dingebre]

I recently acquired an A4000D, Rev B motherboard in amazing condition. It was restored very nicely and was working great (notice "was")

Well, it actually is still running great with a small caveat. I can't seem to get the floppy drive configured properly. Background:

1. The system came with a CF IDE disk with OS 3.1 and 3.9 installed with 3.1 ROMs.
2. It had a CD drive.
3. It had a stock 68040 Amiga 3640 CPU card.
4. It had a 256 Mb RAM card (Individual Computers).

Booted, ran everything great.

I did the following:

1. Added a MTN ZZ9000 RTG card and audio card.
2. Installed 3.2.2 ROMs.
3. Installed the new A3660 CPU card.
4. Configured a new CF card with OS 3.2.2.1.

The PSU also happened to blow up but did not damage the motherboard. It blew the power MOSFET, the PWM chip, a resistor and a couple of fuses, another story . I repaired the PSU and the system seemed to be ok until I reconnected the floppy drive.

After reconnecting the floppy and CD ROM drive, I got a software error during startup. I had NOT changed any jumpers or anything other than installing the 3660, ZZ9000, and ROMs. I read the manual and I have to believe I'm not understanding something I thought I did understand. Right now, jumper J351 is "open" and jumper J352 is set to 1-2 which I understand is an internal DF0: (Changing it to "EXT" didn't really change much).

I have been able to get it booting and recognizing the floppy, sort of. Here are some details of what I've investigated and identified:

1. I disconnected the CD ROM and floppy and it booted fine.
2. Took turns with the CD ROM drive and floppy drive connected/disconnected and saw it was the floppy drive causing issues.
3. I tried the A4000 floppy in my A3000 and it worked fine.
4. I tried the floppy from my A3000 in the A4000 and it behaved the same as the A4000 floppy.
5. I tried a GoTek on the A4000 and it worked.
6. If I install a jumper on J351, DF0: is recognized but I get an "Unreadable DF1:" icon on the workbench.
7. If I set the jumper on the floppy itself to "DF1:" the floppy is recognized as DF1: regardless if I use the middle connector or end connector with or without jumper J351 installed.
8. I can pair the floppy with the GoTek and set either one to DF0: and the other to DF1: and the system sees them how they're jumpered, i.e.: DF0: and DF1:, regardless which one is on the middle connector and which is on the end connector.
9. Jumper J352 doesn't seem to affect what is going on.
10. Jumper J351 does seem to matter. I get the best behavior when it is not installed and I have both the floppy and GoTek.
11. The external floppy port seems to work fine, at least with the GoTek. It didn't seem to recognize a real floppy drive.
12. I tried to go back to 3.1 and am getting similar behavior.

Now for the final weirdness.

1. I can't boot from a floppy or the GoTek regardless which one is DF0: or DF1:
2. I can't double click and hold the mouse buttons and boot into the boot selector screen (sorry, I can't remember the proper name). That is, I hold down both mouse buttons and the system just won't boot. The power light just flashes. This occurs regardless the floppy configuration.
3. I can get it to boot and the system is stable by tinkering as described above. However, it won't boot from the floppy or GoTek nor can I do a double mouse click on power up to select boot options.
4. When I have the configuration such that is is seeing the floppy and/or the GoTek, the system reads and writes to them without issue.

I would greatly appreciate any thoughts or ideas here. I strongly suspect I'm missing something simple.

Thanks for your time and ideas!

David