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[rodneyk]

Hello everyone,

I have been looking at my Supercom Pro.1 again for nostalgic reasons because it was my first introduction into the concept of running SNES games from floppy disks.

I have seen lots of talk about the Supercom and Super Magicom that these have so many similarities and history in common, which also intrigued me a lot.

So I have been testing out a lot of stuff in terms of ROMs, and have been looking into the ROM file format for loading from disk. The "Advanced_SNES_ROM_Utility_v1.1" is somewhat helpful for loading a ROM BIOS from disk, however it will require temporarily enlarging the ROM to above 128kb in order for the tool to accept it.

So far I have not been successful in running a Super Magicom ROM image directly on the Supercom from inside an EPROM. The most I have been able to do is to get the menu of the Super Magicom on the SNES, but not the floppy access which just waited without any response from the drive. Possibly the I/O port address is different between these units, or some other similar type of difference, or even a different FDC chip.

Back in the 90s I had a Supercom Pro.1 with the Supercom Pro.1 ROM in it. I copied this image using a C64 computer, however I seem to have lost it over the years, I spent hours searching my backups, floppies etc but no luck. The Supercom which I bought from Ebay contained the Pro.2 ROM which is as I understand a software update for this same Pro.1 hardware.

Does anyone on this forum have this Pro.1 ROM saved in binary file format? What I am looking for is an actual 8kb binary read of the Pro.1 BIOS ROM for the Supercom Pro.1. My reason to want this is, for historic and nostalgic purposes only, I just want to have fun to try it out and see the differences.

I have examined the hardware inside the Supercom, and there are a few things which stand out regarding the BIOS ROM control and size:
- the Supercom has some means of supporting 8kb or 16kb of BIOS ROM storage.
- the A13 line on the internal BIOS ROM of the Supercom is controlled by one of the outputs of a latch used for the PC parallel port. So a write to this port can flip and hold that bit which goes to the A13 on the ROM and changes between the low and high 8kb banks inside the ROM.
- the "A14" line is permanently low in the Supercom so when using a 32kb (27C256) EPROM for the BIOS socket, only the bottom half is ever able to be addressed.

It's a little weird what I have seen because there are lots of Super Magicom BIOS versions on the internet, however when I look inside these files, some of them have the 512 byte file header at the start for loading from a disk, while others don't. Like, I see some files of 33kb which don't appear to have a typical header with a number of zero values at the start. These files are marked "[o1]" in their name. I am just not seeing a consistent type of binary file between these files found on the internet, when looking inside the files. I suppose some of them may have been dumped by plugging a Supercom into another copier, I don't know.

I'm a little unclear about the Super Magicom because I have never seen one internally. Would it possibly contain a 32KB 27C256 BIOS ROM which is fully supported for access by the SNES? I will try to find some PCB photos which may be able to tell me more about this. The BIOS files I have seen are just varied and not consistent to identify the type of EPROM they come from.

Anyway, I am hoping to find more versions of the actual ROMs found in Supercom Pro.1 hardware. Or for example ROMs which are able to actually run on this copier.

I don't have any "favorite" copier, I basically like them all! I fully realize that the Supercom is in many cases not a useful copier, which I don't mind. I am also going to look at the HiROM modification as discussed on this forum before. I will find some GAL chip and test it out when I have enough time. I will share the experience as soon as I have had the time to do this.

Thanks for any information or interesting discussions about the Supercom / Super Magicom!

Kind regards,

Rodney

[rodneyk]

I have checked more things because I felt something is not right, I was not able to use a Winbond W27C512 to test BIOS images previously.

I found the cause, the A14 line on the EPROM socket is connected to VCC, and not to ground as I previously thought. My information was old and had an error, or that previous Supercom Pro.1 PCB had a different layout, I don't have that old Supercom anymore.

So with pin 1 connected to VCC (A15 on W27C512), pin 27(A14) connected to VCC, in a W27C512 chip with 64KB storage(0000-FFFF), we end up at C000 and above which is accessible by the SNES within this particular chip. There are two blocks, C000-DFFF and E000-FFFF, the lower 8KB and upper 8KB block.

A13 on the socket is controlled by a 74LS174 latch output, and I was not sure what would be the default level of this output. It's normally high.

So that means that the high 8KB appears to be enabled by default when loading the BIOS, or at least initially. The lower bank can be enabled by the BIOS program if that 74LS174 latch bit controlling A13 is set to low by an output command from the CPU, so it's a form of bankswitching with two 8KB banks.

If we have a 8KB BIOS file, it needs to be loaded into the E000-FFFF region when using a 64KB '512 kilobit' type ROM chip. When using a 32KB '256 kilobit' type ROM chip, it would be loaded into the 6000-7FFF region of that chip.

In my case I have a few W27C512 from a Chinese seller so I prefer to use those. This chip can be used in the same BIOS socket without any modifications.

So I was then able to test much faster than by UV erasing 8K EPROMs and had the time to test more ROM images, and keeping track of the results again.

So I can report that:

Super Magicom V1H BIOS, "SUPER MAGICOM V1H" on the screen is working to access the floppy drive and load a simple 8Mbit game file.

Super Magicom V3H BIOS [a1] is not working, I took out 8KB of code from this file which to me looked like the actual BIOS code program, and tested with this.

MDDOS32H, "MAGIC_DOS_3.2H" found in the image, does not work at all, no init/menu. This version is called "SUPER MAGIC DRIVE DOS V3.2H" in the description text file.

ROM-SMC.HIR, "HIROM DOS FIX" is displayed, the floppy drive does not respond when selecting to load a game file.

SMChiROM.BIN "HYPER MAGICOM" (I love this name!) is displayed, the floppy drive does not respond when selecting to load a game file.

So far I can say that the Supercom PRO.1 is at least compatible with the Super Magicom V1H BIOS file found on the internet.

I will search for some PCB photos to possibly be able to see from those how these units compare in broad lines, or even possibly to see if there are different PCB revisions of the Super Magicom or Super Magic Drive.

I will search all my C64 floppy disks today to see if I can find the Supercom PRO.1 version BIOS. This is a slow process but I will check the disks again. If anyone has this PRO.1 version ROM, I would appreciate it if they can send me a copy!

Kind regards,

Rodney

[Mystic_Merlin]

AFAIK the Super Magicom, the Supercom Pro 1 and Supercom Pro 2 are exactly the same hardware. Mostly BIOS have been updated to include more tools to copy entire disks and such.
I have many of these 3 but they are pretty much all updated to the Supercom Pro 2 BIOS, some are even using a UFO 3 BIOS when modified with the Hirom fix.

ROM-SMC.HIR is a modified BIOS that includes the Hirom loader on the Super MAgicom Drive and SMChiROM.BIN the same thing for the Super Magicom.

On the IC2 thread I posted a modified version of the loader to run on Super Magicom clones. I just added a subroutine to load the character table as it's not needed on the Super Magicom.

[rodneyk]

Hi Mystic_Merlin,

It's great to read your reply. Thanks for letting me know about your Super Magicom and Supercom software versions.

I checked my ~200 C64 floppies and finally came across the file I saved from the EPROM of the Supercom Pro.1 back in the 90s. Well, my memory was apparently not so clear after many years because this one was also the Pro.2 version of the BIOS. It was byte for byte identical. So the memory of Pro.1 must have been only from what's on the Supercom printing on the plastic.

I see about the ROM-SMC.HIR and SMChiROM.BIN. I was not able to access the floppy drive with these, though the menu is displayed and responds to the controller buttons.

Thanks for mentioning the MMLOADER.SMC, I have just tested this and it also works on my Supercom, I tested by loading a low ROM game. I will test more later.

I didn't have time to fully study the different address line modifications to understand what the exact result is on the memory map, and if this would impact the I/O to the FDC chip but possibly these modifications are needed to be in place so that the floppy controller will then respond with the modified BIOS versions. I will test these BIOS files again later when I have time to wire in and test with the TTL IC and GAL chip modifications present.

I'm also interested in how the EP1810LC programmed logic works.
I may modify or try to recreate the Supercom later in an SRAM version to test it further. A lot of the stuff in the EP1810LC is just related to refreshing and multiplexing address lines for column and row control of the DRAMs. Using SRAMs will simplify the design a lot. I would be able to use a CPLD/quartus for this purpose. When I first saw the Supercom, I was intrigued to try to find out if I could create one myself. At the time my design experience was too limited but now I have done a lot more work. Not that I want to publish a design but I just want to see if it could work. Using a CPLD it's easier to try out different ideas with possibly only little rewiring needed.

I think understanding the Supercom completely could be a first step in possibly figuring out the Pro Fighter Q which has a lot of DIP programmable ICs. There it's the same thing, lots of DRAM related stuff which could be eliminated for testing out the concept. I just feel it would be cool to see it work one day if I could do it.

Kind regards,

Rodney

[Mystic_Merlin]

Hey Rodney, you should join the Discord TTK server as Modman is currently working on the Supercom

https://discord.gg/aqGdAfwj

[rodneyk]

Hi Mystic_Merlin,

Thanks for the invite link and great to see you there!

Kind regards,

Rodney