NMS 8250 floppy drive replacement

By rvanzon

Rookie (17)

rvanzon さんの画像

08-04-2018, 09:33


After 20 years of storage I tried my NMS 8250 again. It boots up! :-D Damn, I missed this little guy...emulators are cool. But you know...

Only, a lot of disks don't seem to work. I have the idea the reason is not (only) the disks, but it could be the drive. As sometimes it does read. Then, while ejecting a floppy, the metal cover stayed in the floppy drive Question So have to try to get that out.

I wonder what my options are here. I saw some old thread talking about the Sunrise Interface. But it seems dated. As genuine hardware seems to be scarce, at least in the Netherlands, would it be possible to use a PC-drive or something?

Hope someone can help me out here. Thanks!


By Hans41

Expert (71)

Hans41 さんの画像

08-04-2018, 12:17

I don't want to be rude, but there are a lot of threads about this. Wink

A pc drive can easily be used.

You'll need to change the flat cable a little. Line 10 from the controller to the drive needs to be connected to line 12 going to the drive, making the pc drive (by default drive b) acting as an a-drive. And a disk ready signal is needed by the MSX. There a several ways of achieving that. I change the flat cable, but the most popular way seems to be to connect pin 33 and 34 on the controller (on the motherboard, duh).

That's it in a nut shell, but again, there already are a lot of threads covering this. If you use the search option, there probably are more detailed instructions.

By rvanzon

Rookie (17)

rvanzon さんの画像

08-04-2018, 13:32

@Hans41 thanks man. I tried to search. But to be honest, the results confused me. Some advised to use the Sunrise Interface instead of replacing a drive. Then some results were from 2007/20008 with dead links. I don't find the forum of msx.org that easy to use always...

Now I know it's possible, I will dig in some more. Thanks for pointing this out!

By Grauw

Ascended (10821)

Grauw さんの画像

08-04-2018, 14:15

I would recommend getting a MegaFlashROM SCC+ SD or Carnivore or SD-512 or any of the more modern interfaces that can be readily ordered from various places. The Sunrise IDE/CF interface is old and hard to get by, and dated because it doesn’t have Nextor (there is a “beta” Nextor build for it but I haven’t gotten it to work on mine). And the modern interfaces also come with various other features like MegaFlashROM / MegaRAM, extra RAM, sound functions, etc.

If a disk drive doesn’t work anymore it’s often the drive belt that needs replacing, but in your case it sounds like it might be something else.

By Wild_Penguin

Hero (644)

Wild_Penguin さんの画像

09-04-2018, 13:15

Open and oil up the drive! The grease/oil might be old and that migjt explain why it jams.

You might want to look at floppy drive emulators. There are cheap and expensive options out there. Will be cheaper than a MegaFlashRomSCC+Sd (or something else), but you get less features.

Dealing with real floppies is not worth all the hassle IMO. But in case you really need to use a PC drive, at least the nms825x has Shugart compatible drives. Often PCs have jumpers for setting RDY/DSKCHG signal and /DS0, /DS1 (or 2 and 3). This page has loads of information about floppy drives:


Also see msx info pages.

By roadfighter

Champion (467)

roadfighter さんの画像

11-04-2018, 20:22

Wild_Penguin wrote:

.......Often PCs have jumpers for setting RDY/DSKCHG signal and /DS0, /DS1 (or 2 and 3). This page has loads of information about floppy drives:


Also see msx info pages.

Also take a look at

By Josevil

Master (199)

Josevil さんの画像

11-04-2018, 22:29

You have in ebay fdd Samsung SFD-321B with ready for 20e in ebay and it is easy to modify, but the easiest thing would be to use a mgf with sd


By Moniz

Champion (401)

Moniz さんの画像

11-04-2018, 23:19

Have you tried to clean and oil the drive like Wild_pinguin said?
If that didn't do the trick I have a spare original 8250 drive here. It's a bit dusty and could use some cleaning but I've tested it and is fully working!

By rvanzon

Rookie (17)

rvanzon さんの画像

13-04-2018, 15:08

thank you all for your great info!

I don't really want to use floppies in the future. But I have a lot of my own floppies, with MoonBlaster-files, and games I developed back in the day. Just wish to get them back. for ol' time sake Wink I ordered an USB-floppydrive. See if I can access them on my Mac.

The new MSX-hardware is very cool. Will check them out. I think the MegaFlashROM is the best option. They are sold out though Sad So will see what to do.

This weekend I will try to clean the drive...ow and remove the metal part...

Thanks again for your replies!

By Wild_Penguin

Hero (644)

Wild_Penguin さんの画像

25-04-2018, 17:56

A USB drive can work, but some of them are crippled in that they always assume 1440kb disk format (and might not even have the sensor for the HD/DD hole from the looks of it). With those you can not salvage the disks.

Also there might be some OS complications (because of Windowses newer than XP). But I've ditched Windowses, and this has been discussed many times (here and elsewhere), so I'll leave it at that Smile.

Don't know about OS X (I'm certain I've used my USB floppy drive on my Macbook Pro, but that was when it was running Linux).

However, this the way to go if you have some option to ditch using floppies on the MSX and just got some floppies to salvage!