FDC37M60X SMSC Corporation, FDC37M60X Datasheet - Page 64

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

and is not needed for normal operation. Once
the Perpendicular Mode command is invoked,
FDC software behavior from the user standpoint
is unchanged.
The perpendicular mode command is enhanced
to allow specific drives to be designated
Perpendicular
enhancement allows data transfers between
Conventional and Perpendicular drives without
having to issue Perpendicular mode commnds
between the accesses of the different drive
types,
compensation values.
When both GAP and WGATE bits of the
PERPENDICULAR MODE COMMAND are both
programmed to "0" (Conventional mode), then
D0, D1, D2, D3, and D4 can be programmed
independently to "1" for that drive to be set
automatically to Perpendicular mode.
mode the following set of conditions also apply:
nor
having
recording
to
change
drives.
write
In this
This
pre-
64
1. The GAP2 written to a perpendicular drive
2. The write pre-compensation given to a
3. For
Note: Bits D0-D3 can only be overwritten when
Software
following
MODE COMMAND:
1. "Software" resets (via the DOR or DSR
2. "Hardware"
during a write operation will depend upon the
programmed data rate.
perpendicular mode drive will be 0ns.
conventional mode drives any data written
will be at the currently programmed write
pre-compensation.
registers) will only clear GAP and WGATE
bits to "0". D0-D3 are unaffected and retain
their previous value.
(GAP, WGATE and D0-D3) to "0", i.e all
conventional mode.
OW is programmed as a "1".If either
GAP or WGATE is a "1" then D0-D3 are
ignored.
D0-D3
effect
and
hardware
resets
on
programmed
the
will
resets
PERPENDICULAR
clear
to
have
"0"
all bits
the
for