W83787IF Datasheet, PDF (118/123 Pages) Winbond – WINBOND I/O WITH SERIAL-INFRARED SUPPORT

CR22
This register is used to select the base address of the IDE Interface Alternate Status Register from 106H - 3F6H on 16-byte
boundries + 6. The default value is FDH. NCS=0 and A10=0 are required to access the IDE Alternate Status register.
A[3:0] must be 0110b.
bit 7 - bit 2: match A[9:4]. Bit 7=0 and bit 6=0 disable this decode.
bit 1: fixed at zero.
bit 0: fixed at one.
CR23
This register is used to select the base address of the parallel port. If EPP is disable, the parallel port can be set from 100H -
3FCH on 4-byte boundries. If EPP is enable, the parallel port can be set from 100H - 3F8H on 8-byte boundries. The
default value is DEH. NCS=0 and A10=0 are required to access the parallel port when in compatible, bi-directional, or EPP
modes. A10 is active in ECP mode.
bit 7 - bit 0: match A[9:2]. Bit 7=0 and bit 6=0 disable this decode.
CR24
This register is used to select the base address of the UART A from 100H - 3F8H on 8-byte boundries. The default value is
FEH. NCS=0 and A10=0 are required to access the UART A registers. A[2:0] are don't-care conditions.
bit 7 - bit 1: match A[9:3]. Bit 7=0 and bit 6=0 disable this decode.
bit 0: fixed at zero.
CR25
This register is used to select the base address of the UART B from 100H - 3F8H on 8-byte boundries. The default value is
BEH. NCS=0 and A10=0 are required to access the UART B registers. A[2:0] are don't-care conditions.
bit 7 - bit 1: match A[9:3]. Bit 7=0 and bit 6=0 disable this decode.
bit 0: fixed at zero.
877/787I APN 3
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