W83877TF Datasheet, PDF (120/154 Pages) Winbond – I/O chip disk drive adapter

W83877TF
This register is used to select the base address of the Floppy Disk Controller (FDC) from 100H-3F0H
on 16-byte boundaries. NCS = 0 and A10 = 0 are required to access the FDC registers. A[3:0] are
always decoded as 0xxxb.
FDCAD7-FDCAD2 (Bit 7-bit 2): match A[9:4]. Bit 7 = 0 and bit 6 = 0 disable this decode.
Bit 1-bit 0: Reserved, fixed at zero.
8.2.27 Configuration Register 23 (CR23)
When the device is in Extended Function mode and EFIR is 23H, the CR23 register can be accessed
through EFDR. Default = DEH if CR16 bit 2 = 1; default = 00H if CR16 bit 2 = 0. The bit definitions
are as follows:
765
43
21
0
PRTAD0
PRTAD1
PRTAD2
PRTAD3
PRTAD4
PRTAD5
PRTAD6
PRTAD7
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 boundaries. If EPP is enable, the parallel port can be set from
100H-3F8H on 8-byte boundaries. 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.
PRTAD7-PRTAD0 (Bit 7-bit 0): match A[9:2]. Bit 7 = 0 and bit 6 = 0 disable this decode.
8.2.28 Configuration Register 24 (CR24)
When the device is in Extended Function mode and EFIR is 24H, the CR24 register can be accessed
through EFDR. Default = FEH if CR16 bit 2 = 1; default = 00H if CR16 bit 2 = 0. The bit definitions
are as follows:
765
43
21
0
reserved
URAAD1
URAAD2
URAAD3
URAAD4
URAAD5
URAAD6
URAAD7
This register is used to select the base address of the UART A from 100H-3F8H on 8-byte
boundaries. NCS = 0 and A10 = 0 are required to access the UART A registers. A[2:0] are don't-care
conditions.
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Publication Release Date: March 1998
Version 0.61