What kind of Floppy controller is this?

Robin4 · Jan 6, 2015

diodenmann said:
I recently got a NOS bunch of these controllers. Instead of GDC-66 it reads TN-860C on the back but it's the same card.

Can you tell me what kind U5 and U7 are of ?

According to the original manual, I can provide some information:

JP1: PC or PS/2 reduce write current selector

1-2 Select PC/XT or AT
2-3 Select PS/2

SW1:
1 2 3 4
on off on on XT
on off on on AT with HDC installed
off off on on AT without HDC
on off off off PS/2

The manual also mentions explicit support of 360k, 720k, 1.2M and 1.44M drive types.

Are you able to make an image of the onboard rom ?

Do you still have that manual? Would it possible to get a copy or can you make a scan of that manual.? I really like to know if there is more information available.

Robin4 · Jul 10, 2015

I think i know who made this floppy drive controller..

Diodenmann is also selling this LBA controller:

That floppy controller in the first post, comes from the same company called TANS, or TAN.. (i think its TANS exactly)

Thats why there is a TN-860c inside this `type number`

If you are looking right, the type of PCB used is just the same...

I also found these specs about the used controller chip:

Robin4 · Mar 10, 2024

I'm curious if there are people who have this controller working or have gotten it working.I also have this controller card here. But he doesn't.At first I was unsure whether the inserted ICs were the right ones. Because it may well be that the previous owner also had problems with this and therefore could have tried something.I wonder if the BIOS shows a message at startup.And can someone tell me which ICs should be in those sockets to validate whether these are the right ones that should be in them.I also compared various controllers and then I saw that 74LS04N and 74LS30N are very common on a controller.I replaced the top IC for a 74LS04N but the system would no longer boot.I also checked all the ICs with my USB Eprom writer and they all seem to be functioning.Also checked the bios chip and it appears to be full of data.I'm a bit desperate at the moment as to what could be why this card won't work.I also suspected that the 74LS245N might not be good.Read that they can often break the bank.Otherwise maybe a defective floppy controller chip perhaps?I'll see if I can desolder this and provide it with an IC socket.Anyone who would like to help me further?

Robin4 · Mar 10, 2024

It seems the card is working after some fiddleling

Connected a second drive without resistor pack (5.25inch 360KB) to it. But it auto detects it at 1.44MB.. How to fix?

I have set this: (tn-680c card)

SW1:
1 2 3 4
on off on on ( getting 1.44MB on both drives A & B) (connected A: 1.44MB drive connected B: 360KB drive) (card functions)

SW1:
1 2 3 4
on off off on ( getting 1.2 MB on drive A: -- 720KB on drive B: )

SW1:
1 2 3 4
on on on on (getting Drive A: None -- Drive B: None) (doesnt work)

SW1:
1 2 3 4
off off off off (getting 1.2MB on drive A: --- 720KB on drive B: (with a bootdisk failure) Bootdisk seems to be good) (doesnt work)

SW1:
1 2 3 4
on off on off ( getting 1.44MB on both drives A & B) (connected A: 1.44MB drive connected B: 360KB drive) (card functions)

SW1:
1 2 3 4
on on on off (getting Drive A: None -- Drive B: None) (with a bootdisk failure) Bootdisk seems to be good) (doesnt work)

SW1:
1 2 3 4
off on on off (getting Drive A: None -- Drive B: None) (with a bootdisk failure) Bootdisk seems to be good) (doesnt work)

SW1:
1 2 3 4
on off off off ( getting 1.2 MB on drive A: -- 720KB on drive B: ) (with a bootdisk failure) Bootdisk seems to be good) (doesnt work)

SW1:
1 2 3 4
on on off on (getting Drive A: None -- Drive B: None) (with a bootdisk failure) Bootdisk seems to be good) (doesnt work)

Really no 5.25 inch 360KB floppy support? Or bios rom comes from another card maybe> or a poor card design?