IBM XT diagnostic ROM

[Andrew Lynch]

Hi,

Has anyone have or know where to get an IBM XT (5160) diagnostic ROM?  I am
trying to revive an original IBM XT motherboard which is nonresponsive and
gives no error codes (beep or POST).

I am not even sure such a ROM exists but it would be a 27C256 style EPROM
that plugs into an IBM XT motherboard to help fault isolate an almost
completely dead unit.

The motherboard CPU seems to be working based on a quick exam with the
oscilloscope.  However, the motherboard's initialization / boot process is
not making it to start up the video display before it hangs or crashes.
Obviously, something is broken but I haven't isolated exactly what yet.

If anyone can help, I would much appreciate it.  Thank you in advance.

Andrew Lynch