W83C553F Datasheet, PDF (70/159 Pages) Winbond – SYSTEM I/O CONTROLLER WITH PCI ARBITER

W83C553F
Electrical Specifications
Chip Select Control Register (default = 33h)
Type:
Read/Write
Bit Description:
Bit 7:
Bit 6:
Bit 5:
Bit 4:
Bits [3:2]:
Bit 1:
Bit 0:
EBIOSCSE. Extended BIOS Enable.
0= Disabled
1= Memory access from FFF80000h to FFFDFFFFh will assert ROMCS in
PowerPC mode or the encoded output XCS[1:0 = 11 in x86 mode.
LBIOSCSE. Lower BIOS Enable.
0= Disabled
1= Memory access from FFFE,0000h to FFFE,FFFFh or FFEE,0000 to FFEE,FFFF
or 000E,0000 to 000E,FFFF will assert ROMCS in PowerPC mode or the
encoded output XCS[1:0] = 11 in x86 mode.
BIOSWP. BIOS Write Protect.
0= Disabled
1= When set, ROMCS in PowerPC mode or the encoded output XCS[1:0] = 11 in
x86 mode will not be generated for write access to the BIOS space.
UBIOSCSE. Upper BIOS Chip Select Enable. This bit defaults to "1" after reset.
0= Disabled
1= For Revision ID 0, Memory access from FFFF,0000h to FFFF,FFFFh or
FFEF,0000 to FFEF,FFFF or 000F,0000 to 000F,FFFF will assert ROMCS in
PowerPC mode or the encoded output XCS[1:0] = 11 in x86 mode.
For Revision ID 4, Memory access will be from 000F,0000 to 000F,FFFF or
FF80,0000 to FFFF,FFFF..
Reserved.
KBCSE. Keyboard Controller Address Location Enable. .
0= Disabled
1= Access to the I/O ports 60h, 62h, 64h, or 66h will give the encoded output
XCS[1:0] = 11 for keyboard chip select in x86 mode. This bit is reserved in the
PowerPC mode.
RTCCSE. RTC Address Location Enable.
0= Disabled
1= Access to the I/O ports 70-77h will give the encoded output XCS[1:0] = 01 for for
RTC Data Port in x86 mode. This bit is reserved in the PowerPC mode.
WINBOND SYSTEMS LABORATORY
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