Retry Bug in Tarbell CP/M 2.2 and 1.4 (after 2-15-78 version)

When a read error occurs, the BIOS calls a routine that checks for a track seek error. This routine attempts to read an address mark off the disk. 

If an address mark can be read from the disk, a seek is done to the track number read from from the address mark and the sector read is attempted again.

If an address mark cannot be read, the routine restores the disk to track 0 by calling the HOME routine and then attempts to re-seek to the proper track (as specified in a previous SetTrk BIOS call). However, the HOME routine sets the SetTrk value to zero, so instead of seeking back to the proper track, the disk remains at track zero. The sector read is then attempted again, but instead of reading from the proper track, the sector is read from track 0.