Super Magic Drive

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Super Magic Drive
by on (#228158)
I recently aquired a Super Magic Drive for the Sega Mega Drive/Genesis. I thought I would be able to load up a few homebrews and other roms on it from the PC. I know it is possible via the parallel port, but I don't have a PC with one of those. I do however have a floppy drive on my PC (USB floppy drive), so I thought I would be able to use that. However, I can't for the life of me find if anyone has ever successfully got a SMD floppy to read on the PC or the other way around.

If I format the disk on windows it will just give a "read error" on the SMD. If I format it on the SMD, windows refuses to read it.

Is this task impossible? Are they just totally incompatible, like Amiga floppy drives? I have googled like crazy. The device has lots of great info available online, and software to transfer files via the parallel port etc. But nowhere have I found anything regarding transferring files via floppy, which in my head, would be the more straight forward approach :)
Re: Super Magic Drive
by on (#228165)
Do you have a Linux box available? It may be able to detect things better.
Re: Super Magic Drive
by on (#228166)
The floppies should be in standard IBM format and perfectly readable on PC. If you cannot then either one of your drives is misaligned or you're using win7 or newer (which are known to have problems with floppies).
Re: Super Magic Drive
by on (#228168)
Possibilities include:

1. Floppy disk may be bad (seems unlikely though, but try doing a full sector read and write verify using some software you can find -- this should work (don't let the name of the program fool you)),

2. Floppy drive in the SMD may be bad (broken/misaligned heads/tracking). I'm not familiar with what's in a real SMD itself, but many copiers back in the day just had standard run-of-the-mill IBM PC floppy drives in them and were easily replaceable,

3. Bad RAM (or cache) used for reading floppy contents on the SMD -- wouldn't surprise me given the age of these copiers,

4. Extremely wonky floppy drive on the Windows PC. I have actually run into some USB-based floppy drives that completely misbehave (on both XP and Windows 7, i.e. purely a drive thing) -- they would throw I/O errors on reads, but not on writes (i.e. copying a file to a disk would work, but ejecting/reinserting and attempting to read the disk would result in complete failure). I've only seen this happen twice (and two completely different drives!), and both times the system was running XP.

Oh yeah: make sure that the floppy drive isn't wired backwards (cable flipped). If the 3.5" drive has a R/W access LED, if it's wired backwards the LED will be on constantly. Insertion of a disk into a drive in this state will result in the disk contents being completely trashed. If there's no access LED, just put your ear up against it and see if you can tell.
Re: Super Magic Drive
by on (#228172)
Modern Windows versions don't like 720K floppies, and forget about 1.6Mbyte. First, format the disk at 1.44 on the Magic Drive, dump a cartridge game to it and try to reload it. The step after this all works is getting that ROM image on floppy to a PC.
Re: Super Magic Drive
by on (#228183)
I am on windows 10.

If I format a floppy on windows, I can read and write without problems on windows, but the disk is unreadable/unwriteable on the SMD.

If I format a floppy on the SMD, I can save and load games on the SMD without issue. But the disk is unreadable in windows.

So it seems both floppy drives are working OK.

I have of course tried to stay in normal specs, so no fancy 1.6 meg formatting or anything like that.
Re: Super Magic Drive
by on (#228235)
Move the drive from one machine to other to rule out alignment problem, format on SMD and move that drive to the PC, if it still won't work you got a software issue at hand.
Re: Super Magic Drive
by on (#242825)
Update time! I got hold of an old DOS 486 laptop with a real floppy controller. Got it working, even with the 1.6 MB special format! A bit of a hassle, but I dumped the disk with an application called DISK2IMG. Then I transferred the image from the old laptop via a PCMCIA CF-card adapter, the CF card I can read with a USB memory card reader on my Windows 10 PC. Then I used the application Winimage to extract the ROM files. I was also able to reverse the process by creating a disk image with a ROM file on it with Winimage, transferring it to the 486. Then using an application called DSKIMAGE I was able to write the image to disk again.

I have now also opened up and clipped out the battery. It has leaked and caused some corrosion on the PCB, but it still works (for now).

My Super Magic Drive is only 16Meg. Does anyone know if I can build a 24 or 32 meg RAM board for it? Or will the main PCB need mods for it? I can't find much info on this at all. Ah, well. At least a lot of games are playable on a 16Meg one. I am happy now that I can finally produce some floppies!
Re: Super Magic Drive
by on (#242832)
Pictures here: https://videogamedevelopmentdevices.fan ... agic_Drive
show that the 16Mbit of DRAM are stored on a daughtercard. While the ICs on it are standard (4x FPM 1Mi x 4 bit), and it would be easy to figure out how to add another four (or to find some larger ones - two 1MB 30-pin SIMMs should have ICs equivalent to the HY514400 pictured above, or an 8MB 72-pin SIMM should make a suitable donor), I don't know if any of the rest of the firmware and decoding logic will handle more than 2MB of DRAM.

edit: Another source claims that 3MB units have been found, and during the commercial lifetime a 4MB upgrade may have been purchasable.