Last Part - The Fix for MS-DOS 6.22 DOM boot
Another day had passed and I’ve remembered that I have BIOS dumps of other machines like this WYSE. There are many Single Board Computers (SBCs) that use this Geode CPUs and CS5536 companions from where you can get a BIOS dump. I have an extracted DiskROM image for a known system EPX-GX500 that is made to work with DOS 6. In the DiskROM image is the Interrupt 13 ISR. So the easiest way to make this WYSE boot DOS 6 was to swap this DiskROM in the BIOS. This will replace the INT 13 ISR with a good working one. I have done just that! Hurray !!! the WYSE booted into DOS 6.22. The final patched BIOS for WYSE Sx0 - S50 can be found here . Now for someone to make this WYSE work like this, it needs to find a way to burn this BIOS to the SST49LF020A chip , either by using my Arduino programmer , or by the mean of some software. For other WYSE terminals that have similar problems the same method...