View Full Version : IBM PC Clone for S-100

August 7th, 2017, 11:51 AM
Hello All,

I've been tinkering with an S-100 board that is an IBM PC Clone. After receiving some very valuable help from a friend, we've gotten to the point where there's output to the CGA monitor showing the BIOS messages. There's errors regarding the keyboard being dead and un-implemented interrupts. I'm posting the disassembly of the ROM on this forum and am looking for suggestions as to what may be causing these errors. What is the ROM doing to test for the keyboard? Attached is also a screenshot of what gets output to the screen, any feedback appreciated.


August 8th, 2017, 03:16 AM

This POPPY BIOS seems to be an original BIOS for one or another clone. It should work then on any XT compatible clone. Because it doesn't work on your clone, the first thing that comes to my mind is: how does the hardware part regarding the keyboard look like?
If the hardware is different from the PC hardware, either the hardware should be changed or the software. I cannot help you with the hardware but I have the source code for a BIOS that I use on my clones.

I hope this helps a bit.

August 9th, 2017, 11:50 AM
Hello All,

I've been tinkering with an S-100 board that is an IBM PC Clone...

I'm confused. I am not aware of an IBM S-100 board. Is this an S-100 board that has the same footprint of the IBM PC?

August 9th, 2017, 12:00 PM
Could you describe the hardware in more detail? How is the keyboard connected to the system?

I would comment on the BIOS itself but I am convinced that I am not understanding it correctly on a quick glance.