ST-V variants and Multi Bios issues

[extant]

Hi Guys,

I think I need help from the ST-V Gurus.

I have 4 ST-V Boards, visually I can see 2 slight varations on the construction of them, I can swap bios beetween the same type of "construction" but if I swap with one of the others, it wont boot (tried once to swap bios because had one that wasn´t accepting no cartridge and discovered this)

The same happens with the multi bios, only works on one type.

So my questions are:

1 - The are different harware versions??? Beside the BIOS version

2 - There are versions not compatible with multibios???

Thanks

 

[Rom1]

Some STV don't use 27C400 eprom.
You have to check what kind of maskrom it was intended for and select the correct eprom.

 

[extant]

Thanks for the anwser, I will check it