AltairZ80: Corrects bug in ICOM floppy device #524
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A hobbyist found an original FDOS for 8" drives (FD360, FD3712) that has turned up a bug in both the FDC+ and AltairZ80 implementation of the FD3712. In the FDC+, the data pointer into the 128 byte write "shift register" is reset upon receipt of a CLEAR command. The real hardware never resets the shift register, so software should not adjust the pointer either. AltairZ80 may need the same adjustment.
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A hobbyist found an original FDOS for 8" drives (FD360, FD3712) that has turned up a bug in both the FDC+ and AltairZ80 implementation of the FD3712.
In the FDC+, the data pointer into the 128 byte write "shift register" is reset upon receipt of a CLEAR command. The real hardware never resets the shift register, so software should not adjust the pointer either. AltairZ80 may need the same adjustment.