FDC37M60X SMSC Corporation, FDC37M60X Datasheet - Page 61

• Manufacturer Part Number: FDC37M60X
• Description: ENHANCED SUPER I/O CONTROLLER WITH INFRARED SUPPORT
• Manufacturer: SMSC Corporation

pulses. The HLT (Head Load Time) defines the
time between when the Head Load signal goes
high and the read/write operation starts. The
The choice of DMA or non-DMA operations is
made by the ND bit. When this bit is "1", the
non-DMA mode is selected, and when ND is "0",
the DMA mode is selected. In DMA mode, data
transfers are signalled by the FDRQ pin. Non-
DMA mode uses the RQM bit and the FINT pin
to signal data transfers.
Configure
The Configure command is issued to select the
special features of the FDC.
command need not be issued if the default
values
requirements.
of
7F
7F
00
01
02
E
0
1
..
F
..
the
2M
64
56
60
4
..
63.5
FDC
2M
0.5
64
63
1
..
128
112
120
1M
..
8
meet
500K
Table 29 - Drive Control Delays (ms)
256
224
240
16
..
the
A Configure
HUT
128
126
127
1M
1
2
..
300K
26.7
426
373
400
..
system
250K
512
448
480
32
..
61
500K
256
252
254
2
4
..
values
speedselection and are documented in Table 29.
Configure Default Values:
EIS - No Implied Seeks
EFIFO - FIFO Disabled
POLL - Polling Enabled
FIFOTHR - FIFO Threshold Set to 1 Byte
PRETRK - Pre-Compensation Set to Track 0
EIS - Enable Implied Seek. When set to "1", the
FDC will perform a Seek operation before
executing a read or write command. Defaults to
no implied seek.
EFIFO - A "1" disables the FIFO (default). This
means data transfers are asked for on a byte-
by-byte basis. Defaults to "1", FIFO disabled.
The threshold defaults to "1".
POLL - Disable polling of the drives. Defaults to
"0", polling enabled.
interrupt is generated after a reset. No polling is
The values are the same for MFM and FM.
3.75
0.25
2M
0.5
4
..
HLT
change
1M
7.5
0.5
8
..
1
300K
426
420
423
3.3
6.7
..
500K
16
15
..
2
1
with
SRT
When enabled, a single
300K
26.7
3.33
1.67
25
..
the
250K
512
504
508
4
8
.
250K
32
30
..
4
2
data
rate