bios

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brendanraymond
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bios

Post by brendanraymond »

How is the bios pulled from the saturn?

I already have the bios for all regions on my PC... had it for years...

but i was just wondering if the bios can be written the saturn also?
Pulsar_t
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Re: bios

Post by Pulsar_t »

They sell USB cables that allow you to dump the BIOS but writing to the MROM is a whole different kettle of fish. Is it even possible?
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Ziggy
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Re: bios

Post by Ziggy »

Uh, I don't know about the dumper system, but if the BIOS is on a mask ROM it's not like you can flash it anyways. PCs have the BIOS on an EPROM or EEPROM so you can reflash it. I'm thinking the Saturn's BIOS is on a mask ROM like game carts, which cannot be reflashed.

Though not impossible. If you were to find out what kind of EPROM or EEPROM would be a compatible swap for the Saturn's BIOS chip, you could flash a BIOS to a new chip and replace it for the mask ROM BIOS in the Saturn.

brendanraymond, do you want to update (or change) the BIOS version on your Saturn? Or are you just curious?
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Hobie-wan
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Re: bios

Post by Hobie-wan »

Wouldn't that be a BIOS dump for use in an emulator?
brendanraymond
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Re: bios

Post by brendanraymond »

Ziggy

Those are some good suggestions. I would like to be able to change bios versions. If I could get a different bios onto a compatable chip, I would make one for each region and have them on a removeable on an externaly mounted IC Holder. Perhaps I could write to a compatable blank chip with the bios file via my pc using a chip writer.

Just a matter of working out which bios would work with my boards. I also believe that there are too CHIPS I should be interested in. The main system bios ofcourse and the SVT Bios. Is that for the CD reader perhaps? I would then treat that the same with the external IC holder.

I already have 4 system bios files (.bin) and 3 SVT Bios files (.rom) on my PC for emulation.
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Hobie-wan
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Re: bios

Post by Hobie-wan »

brendanraymond wrote:Ziggy

Those are some good suggestions. I would like to be able to change bios versions. If I could get a different bios onto a compatable chip, I would make one for each region and have them on a removeable on an externaly mounted IC Holder. Perhaps I could write to a compatable blank chip with the bios file via my pc using a chip writer.

Just a matter of working out which bios would work with my boards. I also believe that there are too CHIPS I should be interested in. The main system bios ofcourse and the SVT Bios. Is that for the CD reader perhaps? I would then treat that the same with the external IC holder.

I already have 4 system bios files (.bin) and 3 SVT Bios files (.rom) on my PC for emulation.
But there's no point in doing that. If you want to play a different region, use a 4 in 1. STKey, or something similar. Or if you just have to go hacking, rig up switches to the jumper pads. Socketing and burning different BIOS is pointless and expensive. You'd have to open up the system to switch them anyway.
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Re: bios

Post by brendanraymond »

Hobie-wan wrote:
But there's no point in doing that. If you want to play a different region, use a 4 in 1. STKey, or something similar.
Could you tell me a little more info on that please?

I also have the switched the jumper pad... but I was wanting to know how to change it from PAL to NTSC and to 60Hz display
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Hobie-wan
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Re: bios

Post by Hobie-wan »

If you're trying to switch PAL to NTSC, you'll have to do the jumpers inside or the switchless mod I believe. Though I only play Japanese imports, so I just use a cart since I'm not switching TV formats.
brendanraymond
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Re: bios

Post by brendanraymond »

Yeah, I tried that but doesnt work.

it changes the region lock but doesnt change the output from PAL (50Hz) to NTSC (60Hz)

but dont worry, I already found a better saturn site with some good write ups...

http://www.mmmonkey.co.uk/console/sega/saturn5060.htm

Im also gonna pull digital audio from this baby :D

http://gamesx.com/wiki/doku.php?id=av:saturn_sp_dif
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Ziggy
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Re: bios

Post by Ziggy »

Yeah, I would just use a cart to play other regions, or the internal mod works too. If you were to have multiple BIOS chips, what I would do is stack them on the board and wire the /OE leg of each EPROM to a switch so you don't have to physically remove and replace EPROMs every time you want to switch a region. You would only have to flip a switch.

THAT being said, if you just do a region mod all you would have to do is flip a switch anyways, so there's no real point in changing the BIOS. What's more, I don't think the system will boot with a different region BIOS anyway. Lets say you have an American console and you put a PAL BIOS on it. The jumpers are still set to the other region, so I don't see how it would work. You need to change the jumpers, not the BIOS.

I though you wanted to change the BIOS for some kind of revision thing, but if all you want to do is play import games, the region mod is the only way to go (other than a 4-in-1 cart). I link you some more guides from mmmonkey's site...

50/60Hz mod:
http://www.mmmonkey.co.uk/console/sega/saturn5060.htm

single switch JPN/USA/EUR mod:
http://www.mmmonkey.co.uk/console/sega/saturnregion.htm

"ultimate switchless saturn mod"
http://www.mmmonkey.co.uk/console/sega/ ... timate.htm

And if you want to go the cart route, I recommend this one:

http://www.amazon.com/gp/offer-listing/ ... dition=new

That's the one I have. It will boot different regions, give you 1 and 4M video memory for such games that require it, and allow you to use cheat codes as well. The GameShark will also allow you to boot other region games, but you should NOT use one. The GameShark WILL damage the Saturn's cart slot.

edit: We posted the at the same time, but here's the info all the same. :)
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