RELATIVE SEEK
DATA BUS
PHASE
R/W D7 D6 D5 D4 D3
D2
D1
D0
REMARKS
Command
W
W
W
1
0
DIR
0
0
0
0
0
1
0
1
1
1
HDS DS1 DS0
─────── RCN ───────
DUMPREG
DATA BUS
PHASE
R/W
D7
D6
D5
D4
D3 D2
D1
D0
REMARKS
Command
W
0
0
0
0
1
1
1
0
*Note:
Registers
placed in
FIFO
Execution
Result
R
R
R
R
R
R
R
R
R
R
────── PCN-Drive 0 ───────
────── PCN-Drive 1 ───────
────── PCN-Drive 2 ───────
────── PCN-Drive 3 ───────
──── SRT ────
─────── HLT ───────
─────── SC/EOT ───────
D3 D2 D1 D0 GAP
EIS EFIFO POLL
─── HUT ───
ND
LOCK
0
0
WGATE
── FIFOTHR ──
──────── PRETRK ────────
READ ID
DATA BUS
D5 D4 D3
PHASE
Command
R/W D7
D6
MFM
0
D2
0
D1
1
D0
0
REMARKS
Commands
W
W
0
0
0
0
0
0
1
0
HDS DS1 DS0
Execution
Result
The first correct ID
information on the
Cylinder is stored in Data
Register
R
──────── ST0 ────────
Status information after
Command execution.
Disk status after the
Command has
completed
R
R
R
R
R
R
──────── ST1 ────────
──────── ST2 ────────
──────── C ────────
──────── H ────────
──────── R ────────
──────── N ────────
PERPENDICULAR MODE
DATA BUS
SMSC DS – FDC37N3869
Page 42
Rev. 10/25/2000