First post, by keropi
I recently got a Soyo 4SA2 motherboard and I was wondering what the latest BIOS is for this mobo - and if anyone made a LBA48 HDD patch?
I found some BIOS files on retronn.de -> ftp.retronn.de/mirrors/www.elhvb.com_mobokive/Soyo/bios/486/
4sa-iob1.bin seems to be the latest official one from 1995
4sa0730.bin seems to be a 1997 one but no idea what was added/patched
If anyone knows more about it please reply , the board seems very nice.
I added the missing components so now the board has a working ps/2 mouseport - I just followed madowax's instructions 🤣
inductors and 47pf caps stolen from a dead ss7 mobo, added the extra 4.7k pullup resistors for the mouse data and clock lines and connected keyboard controller pin36 to the IRQ12 pin on an isa slot. The stock BIOS did not have mouse functions enabled so I used modbin but the later ones above have it enabled by default.
Everything with a pink dot was added to make the ps/2 header working, maybe it helps someone else to add the components:
I am now also wondering if removing D2 will prevent the battery from charging like it was with the 4SAW2 mobo - so I can just solder a CR2032 and call it a day....