82077AA Datasheet, PDF (21/62 Pages) Intel Corporation – CHMOS SINGLE-CHIP FLOPPY DISK CONTROLLER

82077AA
Phase
RW
D₇
Result
R
R
R
R
R
R
R
Command W
MT
W
0
W
W
W
W
W
W
W
Execution
Result
R
R
R
R
R
R
R
Command W
0
W
0
Execution
Command W
0
Result
R
R
Command W
0
W
W
Command W
0
W
0
Result
R
Command W
0
W
0
W
Execution
Command W
0
W
0
W
0
W
Table 5-1 82077AA Command Set (Continued)
DATA BUS
D₆
D₅
D₄
D₃
D₂
D₁
D₀
SCAN LOW OR EQUAL (Continued)
ST 0
ST 1
ST 2
C
H
R
N
SCAN HIGH OR EQUAL
MFM
SK
0
0
1
1
0
0
C
H
R
N
EOT
GPL
STP
1
0
1
HDS
DS1
DS0
Remarks
Status Information
After Command
Execution
Sector ID Information
After Command
Execution
Command Codes
Sector ID Information
Prior to Command
Execution
Data Compared
Between the FDD
and Main-System
ST 0
ST 1
ST 2
C
H
R
N
Status ID Information
After Command
Execution
Sector ID Information
After Command
Execution
RECALIBRATE
0
0
0
0
1
1
1
Command Codes
0
0
0
0
0
DS1
DS0
Head retracted to Track 0
Interrupt
SENSE INTERRUPT STATUS
0
0
0
1
0
0
0
Command Codes
0
0
SRT
0
0
0
0
0
0
0
0
ST 0
PCN
SPECIFY
0
0
0
1
HUT
HLT
SENSE DRIVE STATUS
0
0
0
0
ST 3
1
0
HDS
DS1
SEEK
0
1
0
0
NCN
1
1
HDS
DS1
CONFIGURE
0
0
1
0
0
0
0
0
EIS
EFIFO POLL
PRETRK
0
1
0
0
FIFOTHR
Status information at the
end of each seek operation
1
Command Codes
ND
0
Command Codes
DS0
Status information about
FDD
1
Command Codes
DS0
Head is positioned over
proper Cylinder on Diskette
1
Configure Information
0
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