![]() two second wait, the loop terminates and returns a general error which is returned by the floppy handler as CF=1, AH=80h, ' Drive timed out, assumed not ready'. If there is no FD interrupt within the ca. Good or bad, either way (CF=0 if good, or CF=1 when bad). When the interrupt occures, the interrupt routine sets the flag, which again breaks the wait loop. The only interrupts possible here hit when the drive has found the desired track (or track 0). Whenever a Seek or Recalibrate/Reset is issued, the 8088 goes into an active wait loop, looking for a flag which is set whenever a disk interrupt occures. My bet would be on a missing track 0 signal. ![]() So I say the FDC doesn't return from whatever command (usually Seek) is issued. INT 13h timeout ( 80h) occures whenever the 'Wait for Interrupt' BOIS routine doesn't detect an interrupt within 2 seconds. You might never be able to read those floppies. Since Windows 95 originally came out in 1995, that is over 7 years and it is quite a 'ancient' amount of time. Floppy drives tend to get their read / write heads out of correct alignment. ( Caveat: The following information is strictly only true for the XT BIOS, not 100% sure about the XT286, but I'd say it is as compatible here as the AT is) Conclusion from above messages: Floppy disks are a 'magnet' media and the 'magnet charge' can 'dissipate' from 'years' of non use.
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