exxos's Atari, Amiga & retro forum

I'm trying to repair an STFM. The original disk drive is dead, so I am trying to use my spare one from the Falcon (EPSON SMD-300 - labeled also SMD340-601).

I figured out that I have to flip the floppy cable by 180 degrees already.

I think the jumper settings also matter. It is set to drive 0, an capital i is jumpered and an H letter.

If I change H to L then at least the Atari detects the drive and can work with it. But each disk is displayed to be empty (0 bytes in 0 files). Of course these are old disks, but usually, there should be something?!

Probably I'm still missing something here? Of course, the ST itself could also be broken.

I have seen similar issues. Where floppies written on a old 720k drive don't display contents on a HDD.

Yeah, looks like that. But also the ST seems to have issues. I wonder which chip is broken when the desktop shows up but without disk drives (super fast after boot). I changed the WD disk controller already.

If the WD is missing completely, I get two bombs on a white screen.

Most of the time it's bad cables.. Bad 720k drive.. Or older drives with belt broken.

The issue was a partially non-working GLUE chip. Besides the non-working drive, the key click sound was missing or wrong, which pointed to a non-working chip-select for the YM sound chip. The non-correct sound chip select also resulted in a non-working drive select as this signal is also generated by the sound chip. I took the GLUE chip from another ST, it has a different ATARI identifier, but so far works without issues.