GM82C765B Datasheet, PDF (27/36 Pages) Hynix Semiconductor – FLOPPY DISK SUBSYSTEM CONTROLLER

GM82C765B
TABLE 20. SCAN HIGH OR EQUAL
PHASE
COMMAND
R/W D7 D6 D5 D4
W MT MF SK 1
W
XX XX
D3 D2 D2 D0
REMARKS
1
X
1
HS
0
US1
1
US0
Command Codes
W
C
Sector ID information prior to command
W
H
execution.
W
R
W
N
W
EOT
W
GPL
W
STP
EXECUTION
Data transfer between FDD and main
system
RESULTS
R
R
R
R
R
R
R
STO
Status information after command
ST1
execution.
ST2
C
Sector ID information after command
H
execution.
R
N
TABLE 21. RECALIBARTE ^∗
PHASE
COMMAND
EXECUTION
R/W D7 D6 D5 D4
W
00 00
W
XX XX
D3 D2 D2 D0
REMARKS
0
X
1
HS
1
US1
1
US0
Command Codes
Head retracted to Track zero
TABLE 22. SENSE INTRRUPT STATUS
PHASE
COMMAND
RESULTS
R/W D7 D6 D5 D4
W
00 0 0
R
TABLE 23. SPECIFY
D3 D2 D2
01 1
D0
REMARKS
1 Command Codes
Status information about the FDC at
the end of seak operation
PHASE
COMMAND
EXECUTION
R/W D7 D6 D5 D4
W
00 00
W
SRT
D3 D2
00
HLT
D2 D0
1
1
HUT
ND
REMARKS
Command Codes
Head retracted to Track zero
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