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AltairZ80: Corrects bug in ICOM floppy device

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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.
This commit is contained in:
Patrick Linstruth
2026-01-16 05:08:38 -05:00
committed by rms47
parent ead27b6d9b
commit f5a6fd869c
1 changed files with 0 additions and 2 deletions
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2
AltairZ80/s100_icom.c
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@@ -1434,8 +1434,6 @@ static uint8 ICOM_Command(UNIT *uptr, ICOM_REG *pICOM, int32 Data)
pICOM->status &= ~ICOM_STAT_DRVFAIL;
pICOM->status &= ~ICOM_STAT_CRC;
pICOM->status &= ~ICOM_STAT_DDM;
pICOM->rDataBuf = 0;
pICOM->wDataBuf = 0;
break;
case ICOM_CMD_LDCONF: