ACT apricot - Page 112

FLOPPY DISK INTERFACE
Status Register. The format of the Status Register following
a head positioning
command is as detailed below. On
issuing a command to the Command Register, the FDC
resets
the Status Register to monitor certain status
conditions implied by the new command. Due to internal
timing delays, the Status Register does not contain valid
status information, until 14 JLS after the new command is
issued.
I s71 S6 11 I S41 S31 S21 SI I SO I Status Register
I ~Inde:USY
LTraCkO
i..-...--CRC Error
L....---Seek Error
------ Protected
'-------Not Ready
Busy A logic high on Busy indicates that the
command is in progress; logic low indicates
that the command sequence is complete.
Index Inverted copy of
the Index Pulse input from the
disk drive. Logic low when the pulse occurs.
Track 0 Inverted copy of the TitOO input from the drive.
CRC
Error
Logic
high indicates that the head is positioned
over
Track o.
Logic high indicates a CRC error was detected
within a sector ID field during verification of
the track.
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