W83787IF Datasheet, PDF (17/123 Pages) Winbond – WINBOND I/O WITH SERIAL-INFRARED SUPPORT

W83787IF
IDE and FDC Interface, continued
CS1
HADSEL
IRTX3
95 I/O
O
During normal operations this pin is used to select the IDE controller.
CS1 decodes the HDC addresses 3F6H and 3F7H (376H, 377H).
During power-on reset this pin selects the HDC address and is pulled
up internally.
When set to high, it selects I/O port address range 1F0H-1F7H
(3F6H-3F7H) (default).
When set to low, it selects I/O port address ranges 376H-377H and
170H-177H.
CS0
IDEEN
IRRX4
CS1 can be programmed by CR0D register as output pin IRTX3 for
serial infrared communication.
94
O During normal operation this pin is used to select the IDE controller.
I CS0 decodes HDC addresses 1F0H-1F7H (170H-177H).
I During power-on reset this pin is pulled down internally and used to
enable or disable the IDE.
When it is set to high, IDE is disabled.
When it is set low, IDE is enabled (default).
WE
DIR
HEAD
RWC
WD
CS0 can be programmed by CR0D register as input pin IRRX4 for
serial infrared communication.
85 OD Write enable. An open drain output.
89 OD Direction of the head step motor. An open drain output.
Logic 1 = outward motion
Logic 0 = inward motion
88 OD Head select. This open drain output determines which disk drive
head is active.
Logic 1 = side 0
Logic 0 = side 1
87 OD Reduced write current. This signal can be used on two-speed disk
drives to select the transfer rate. An open drain output.
Logic 0 = 250Kbps
Logic 1 = 500Kbps
When bit 5 of CR9 (EN3MODE) is set to high, the three-mode FDD
function is enabled, and the pin will have a different definition. Refer
to the EN3MODE bit in CR9.
86 OD Write data. This logic low open drain writes precompensation serial
data to the selected FDD. An open drain output.
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Publication Release Date:Sep 1995
Revision A1