EPR-23609B Bios on downloads section

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OldFoo

EPR-23609B Bios on downloads section

Post by OldFoo »

Guys that bios is not Rev B,



Its a Rev A Japanese bios so the part number is incorrect too..
OldFoo

Post by OldFoo »

Thanks for the heads up!
OldFoo

Post by OldFoo »

How do you know? It doesn't say in the test menu screen.
OldFoo

Post by OldFoo »

If someone is kind enough to send me the correct dump i will fix it asap.
OldFoo

Post by OldFoo »

joshua3dg wrote:How do you know? It doesn't say in the test menu screen.


Test screen shows Japan, I checked the code for the version... everything in the code matches the REV A bioses apart from the region info...
OldFoo

Post by OldFoo »

This post prompted me to compare the known bios roms to see how similar/different they are. I found that, in the same revision, all of the code is the same except a few hex codes. I think this is where bios region can be set/modified. I will study these differences a bit more to see if I can manipulate the region coding. :D
OldFoo

Post by OldFoo »

I'd like to have a NAOMI Uni-BIOS go Josh!!!! :smt020
OldFoo

Post by OldFoo »

You only need to change 1 byte to alter the region code.



2 second job.
OldFoo

Post by OldFoo »

DJ Infinity wrote:I'd like to have a NAOMI Uni-BIOS go Josh!!!! :smt020


It doesn't make it any easier to do! Id imagine a lot of people knew where the region info was. I know i've known for a long time and didn't realise most other people didn't



I suppose you would have to write a program for the Naomi to boot, then say copy the real bios to ram, then you select the region, your program patches the code in ram with the region info you selected and then launches the bios from Ram rather than rom.. Not sure how that would go as I'm no programer :D
OldFoo

Post by OldFoo »

Ordyne wrote:
DJ Infinity wrote:I'd like to have a NAOMI Uni-BIOS go Josh!!!! :smt020


It doesn't make it any easier to do! Id imagine a lot of people knew where the region info was. I know I've known for a long time and didn't realise most other people didn't



I suppose you would have to write a program for the Naomi to boot, then say copy the real bios to ram, then you select the region, your program patches the code in ram with the region info you selected and then launches the bios from Ram rather than rom.. Not sure how that would go as I'm no programer :D


With the price of Naomi 1 mainboards, it just as cheap and easier to have different Naomi's for different regions..



If we could use 27c322 we could at least have a switch like on the STV Bios, but it seems to want the vendor/device id to match.
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