Bios replacement on a VA0 Pal Saturn

[ukrobbie]

Good day, 

I was wondering if any body knows if I can install a region free small bios chip onto a dip VA0 motherboard with out using a dip chip? 
The reason I'm asking is I have a spare small region free chip that I have brought of eBay. I have already installed the same chip into one of my other Saturns that works lovely. But it seems that the chip is not the same for the VA0. So saves me going out trying to find a dip chip. Can I just use the small region free chip that I have laying around? I have already taken the dip chip of the VA0 motherboard and was going to install a 28 pin socket for the new dip chip. If I can't solder a normal small chip in and can find a dip chip from somewhere. That is hard to find in the UK, Unless anybody knows where to find one. 

Sorry for sounding confusing.

Anyway thank you for your help.

[zyrobs]

You'll need a 40pin SOP to DIP adapter, that matches the pin pitch of the bios chip. I think this one would work, from the top of my head the bios chips have a 1.27mm pitch, you should verify that on the specs sheet.
www.proto-advantage.com/store/product_info.php?products_id=2200252

But it is probably cheaper to just buy a DIP version region free bios. Bad_ad84 sells them in the UK for sure, I can send you one too but I'm in mainland Europe (also I'm not sure if I have any 27c4000 chips left).

[ukrobbie]

Thank you very much for the reply,
I have been looking online and actually found a dip bios that I'm hoping will work after thinking about it all. Like you have said it would be better just to get a dip bios then messing about with the chip I have. 

Anyway the chip I have gone for is from this website: www.otakus-store.net/en/modding-products-kits/348-975-region-free-bios-for-sega-saturn-so-or-dip-package.html#/190-version_ou_typer_generique-so

I have also brought a 28 pin IC socket set, so I don't need to solder the chip onto the motherboard and if anything goes wrong I can easy take it out and replace it. 

I just hope that chip will fit. lol

You wouldn't know how to make them different boot sounds at all, different animation menu sounds, do you? 
When I first installed the region free bios chip on my other Saturn, I must have done something and all the sounds of the OS was way different.
Now I really don't know how I have done it, It had great sounds it was and had pretty cool Animation to the CD Menu.
I'm just wondering if there was something you have to press to unlock it maybe?

Thank you

[zyrobs]

Not sure why you went for the 28pin adapter when the bios chips are 40pin.

There are a few different version region free boot roms. There's one from the Japanese units, v-saturns, hi-saturns, usa/pal/korea units, etc. The bootup animation is different between a bunch of them. It sounds to me that you replaced a PAL units boot rom with that of a Japanese ones (or vica versa).

[linkt101]

Is it not possible to upload a Bios using the AR Comms port?

[zyrobs]

No, the bios is stored in non-rewriteable mask rom (or for some very old models, UV EPROM). You have to physically replace it.

You can read it out from the AR Comms port, though.

[dj898]

so how well these freeBIOS chip work?
My Saturn has the ROM chip on the IC socket on the motherboard so replacing the ROM chip is simple swap.

[zyrobs]

Nov 20, 2018 1:38:48 GMT dj898 said:

so how well these freeBIOS chip work?
My Saturn has the ROM chip on the IC socket on the motherboard so replacing the ROM chip is simple swap.

They have the region code check routine in the boot rom edited out. This allows everything that can boot on the system to ignore region code, so not only games but things like video cd cards can boot too regardless of region.

However games that check the region later on to do things, they will still see the old region code. So for ex. if you boot the US version of Die Hard Arcade on a region free Japanese machine, you get some Japanese text. Or if you boot the first print of Soukyugurentai on a region free US machine, you get that glitched English version leftover from the arcade units that called the game Terra Diver. But those are the only two games I know to behave different depending on region (I checked the full US run and most EU games on a Japanese machine, and at least a hundred JP games on a PAL unit).