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Super Famicom Box - PSS cartridges questions + specs

Impendo64

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Hi everyone !

Sorry to bother you but is there someone here that could maybe help me with some questions about the Super Famicom Box ? :)

Those questions are mainly related to the cartridges and to the coin box :)

Many thanks !!
 

HI_RICKY

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it a total different hardware design
there 3 part section combo in 1 box
1 . custom layout SFC ,
2 . special coin program board to SFC for coin box
3 . TV switch , it like SFC link VTR , it in over lay

btw . there have 4 cart
base come with box , main cart with 3 different cart in slot 2
total if looking get it all , 3 set SFBOX is must :)
 

Impendo64

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Thanks a lot HI_RICK :)

I've bought a SFBOX with 3 carts (PSS-61,PSS-62 and PSS-63).

My main question was: in the PSS cartridges, I saw that they are 12 SNES rom slots on it

pss_62_02.jpg

--> this picture comes from the PSS-62

I was wondering if someone already tried to solder an SNES rom on one of the free slots to see if they can be booted on the SFBOX :) .


About the coin box : is there a way to configure it to accept other coins than 100 Yen ? (if not, does the hardware of the coin box can be changed ?).

Sorry for all those nooby questions ^^' .
 
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HI_RICKY

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you need reprogram PSS title menu when you put new rom slot
coin box you need mod turn to size fit what in
 
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Impendo64

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Thanks again HI_RICKY for your reply :) .

So, if there's a way to reprogram the PSS title menu, I would be interrested in it :) . I don't think that there's a way but I can still dream ^^'.

For the coin box, I'll try to mod it then :)

Thanks again ! :D
 

HI_RICKY

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it not hard , if you already buy 3 box , you have 2 box to mod(e.g.. RGB /S-video ), and get more slot 1 cart for mod menu :)
 

Impendo64

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Didn't thought about that point of view :unsure: interesting !

Thanks again !! :D
 

Trimesh

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You can't just add an additional ROM to to the board and expect it to work.

The PSS-61 cart has a special "game" that runs the attract mode - that reads information from the GROMs on each board to populate the menu. I know at one stage there were some people picking the contents of the GROM apart to figure out what it all meant, but I don't know how far they got. I know it contains stuff like the banner graphics for the game and the help text, but not much beyond that.
 

Impendo64

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Thanks for your reply Trimesh

I knew that it wouldn't be so easy but just wanted to know if someone already did that and how :) .

I didn't knew that the attract mode was directly on the PSS-61. I thought it was implemented directly in the mainboard of the SFBOX just like in the FBOX ^^.

If someone know if those people who worked on the GROM documented their stuff, I would be interested to see how far they went :)

Thanks again for your informations ^^ .
 

HI_RICKY

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PSS-61 is special , because it look like master cart,
GROM boot it relocate 3 game in main cart, other 2 will call option cart PSS-62,63,64
the point is here , is GROM already have all PSS info ? if not how PSS cart map the data to GROM ? by SRAM ?
if it a map data , good chance make custom option cart to fun :)
 

Impendo64

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It will probably need a lot of reseaches and some work on the GROMs...

I'll see if I can manage to dump firstly the GROM1 and then maybe the others :)

Thanks again :)
 

gorgyrip

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All the groms are allready dumped. expect pss64.
There aren't 12 roms on the pcb. only 6 mapped hi and lo. CE lines are connected together and after that to some logic ICs. OE lines go to the GAL/EPL.
Replacing the roms it's not easy at it seems. The easiest way it's to replace a rom with something equivalent. Like donkey kong with donkey kong 3.
The FX chip in pss61 uses oe from roms 1 and 2.
The grom has a checksum at the end and it's xored by FF. The graphics are compressed.
The biggest progress i've made was to add 3 games on a pss62 pcb. I've abandoned the project a long time ago. (I was hoping to get 6 roms working, but no luck).
I don't remember, but I don't think it's possible to add rgb. It's been a while and I might be wrong, but the snes outputs svideo to an overlay ic (no datasheet available, but there a datasheet to simmilar one) and that ic doesn't support rgb.
PS: If you compare the boards, you'll see that on pss63 and 64 some 74 chips are missing. A few of them are for fx/dsp and i believe the rest of the missing ones are for the sram (128k sony). It's weird that they are present on pss62 (maybe had an extra of pss61 boards and used them to make pss62...)
The menu text is located in the attract rom and it's also compressed. There is a tool made by the guy that made lunar magic (forgot his name) and with that i managed to decompress some tiles, but when i recompressed them, they displayed as garbage.
 

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HI_RICKY

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thank share info , very useful :)
 

Impendo64

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Really impressive infos !! And it's really cool that you've managed to to make apprear a other game on the title menu !! :oops: Really amaizing !!

Thanks for the infos ^^
 

gorgyrip

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No problem. The title menu can display many titles. I think I've added about 7-8 games for the second cart menu. The bad part is that it doesn't boots more than 3 games for the second cart. I think that can be fixed really easy by someone who has basic programming experience. Sadly there's no interest in the sfc box.
 

Impendo64

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Thanks again for your infos gorgyrip :)

If you may have some links to share that have already some tools, I would be interested to see what has already been done :) . I can maybe give it a try on that code ^^
 

gorgyrip

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It's been a while, but i remember that there was a webpage (it looked like plain text) that explained really good the grom format. I hex edited some random bytes on the part for loading the tiles for the banner and after some tries it loaded uncompressed tiles. I had to move some things around to fit the uncompressed tiles, but it worked. A friend of a friend of mine made a simple msdos program that loads the grom and displays the checksum and xor result and after that i had to manually insert those values into the grom (the last 4 bytes). I've kept some notes, but I don't know where they are.

On the beginning of the grom there's the number of roms, pointers to the rom info and a value from 00 to 03 that determines in what slot is the rom. I've tried to edit that value up to 40 in hex but it loaded from the same slots. Also, let's say I use value 01 for the rom slot. In that case the actual rom can work in 2 different slots (like slots 2 and 4). I don't know who uses/determines those values for the rom slot. Is it he GAL/EPL or the attract rom?

In grom, the rom info starts at 1000, 2000 and so on.
 
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Impendo64

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On the beginning of the grom there's the number of roms, pointers to the rom info and a value from 00 to 03 that determines in what slot is the rom. I've tried to edit that value up to 40 in hex but it loaded from the same slots. Also, let's say I use value 01 for the rom slot. In that case the actual rom can work in 2 different slots (like slots 2 and 4). I don't know who uses/determines those values for the rom slot. Is it he GAL/EPL or the attract rom?

--> It seems that the number or roms is coded in 2bits, which can explain that it only accepts 00 to 03 (00,01,10,11) but it's hard to tell just like that ^^. I'll need to see some dumps (it's the first time that I try to understand SNES ROM files...)

But thanks again for your reply :)
 

gorgyrip

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--> It seems that the number or roms is coded in 2bits, which can explain that it only accepts 00 to 03 (00,01,10,11) but it's hard to tell just like that ^^. I'll need to see some dumps (it's the first time that I try to understand SNES ROM files...)

But thanks again for your reply :)

Do you know how to program?
 

Trimesh

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It's been a long time since I looked at this, and unfortunately I don't have my SFC box any more, so I can't check. I do remember that the main board of the unit (the one right at the bottom) contains what's basically a standard Super Famicom chipset and a couple of other chips - one is a Hitachi Z180 clone and the other is a Fujitsu OSD chip. The PROM for the Z180 is installed on a sub-board that also has some battery backed up RAM and a RTC chip. When you first turn it on, the text that appears is generated by the Z180 - you don't need anything running on the Super Famicom side of things (although it does need to be out of reset because the video is generated as an overlay and it needs the sync signals from the PPU2).

You could try asking Martin Korth - I think he was reverse engineering this stuff at one point, and he's very good at it...
 

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