Instructions to repair or replace HB-F900 Floppy Drive(s)?

Expert (124)

12-05-2021, 02:14

Is anyone aware of instructions for repairing these drives or of suitable replacement drives? Mine just replies with "Disk Offline" when I try the FILES command in BASIC. I need this computer to back up at least one undumped game that I have.

By sdsnatcher73

Prophet (3962)

12-05-2021, 06:36

From what I hear you can use a PC drive that is modified for MSX that includes also the RDY signal. Although if just for dumping one without RDY may work as well. I have tested some MSX converted drives in F700 and the drive works but on boot into BASIC it freezes the machine until you insert a formatted floppydisk. Booting a game or DOS works fine.

By BitSquad

Expert (124)

12-05-2021, 21:09

Now my understanding is that I would have to use a Sony MSX because the drives that were used in Panasonic computers don't allow me to bypass the copy-protection. So if I switched the drives, there would be no guarantee that I'd even be able to use the new drives to accomplish what I want to, right?

By Manuel

Ascended (19469)

12-05-2021, 21:27

You need an MSX with a WD2793 floppy drive controller (FDC) and a connection scheme (how the FDC registers are mapped into memory) that is supported by the DMK Creator program.
The drives themselves are always OK, as long as they work normally on the MSX. So if you got a working drive on your HB-F900 it will almost certainly work with DMK Creator.

Most (if not all) Panasonic machines have a TC8566AF FDC, so they are not suitable. Sony machines have the WD2793 and the (common) connection scheme is apparently supported by DMK Creator.

By BitSquad

Expert (124)

12-05-2021, 21:30

Does the FS-A1GT use the TC8566AF?

That's the only one that I own with a working floppy drive but it's still in Japan at the moment. After all these years I'll finally be able to play a floppy disk game off an actual floppy disk. So far I've only played floppy disk games on my 1chipMSX.

By Manuel

Ascended (19469)

12-05-2021, 21:35

Yes, it does. To my knowledge, all of the Panasonics have that FDC, alas. (But I was a bit careful as I'm not 100% sure that perhaps some very uncommon and unemulated machines may have another one.)

Anyway, as I said in the other thread, it should be very easy to replace the disk drive of your Sony, just try to get a few of these drives and try them out Perhaps the first one already works, like on my G900P back then!

By luppie

Paladin (869)

12-05-2021, 21:59

If it is the same drive as the Turbo-R (or Panasonic generic) then these instructions might help.

https://www.msxinfo.net/2013/06/09/replace-a-msx-turbo-r-dis...

And a post of an other machine, but with the same controller.
https://www.msxinfo.net/2013/06/13/adding-a-second-drive-to-...

Maybe You can track and map the pinout to a PC drive.

By Manuel

Ascended (19469)

12-05-2021, 22:22

If the drive in the HB-F900 is the same as the HB-G900P (which is likely), it's just a standard 34-pin shugart connector that will fit on any standard 3.5" disk drive. That's why I think it is probably very easy to replace.

@luppie: the FS-A1GT doesn't need a drive replacement, but his Sony HB-F900 does

By BitSquad

Expert (124)

12-05-2021, 23:08

That's correct. It's the Sony that I need a replacement for. I've got the drives out but haven't put anything else in their place yet.

For the replacement, I need to make sure that the drive supports ready signal, right?

Thank you for the help!

By Manuel

Ascended (19469)

12-05-2021, 23:41

You can try it out safely. Just open the machine and connect the power and the 34-pin connector and try it out.
I have no experience what happens with/without ready signal, but someone else said something about it earlier, I think.

By BitSquad

Expert (124)

13-05-2021, 00:32

Well, here's a fun new problem. I think I broke the computer somehow. It boots with a red background and doesn't load BASIC. So it doesn't look like there's much chance of this working. I can't run any programs.