w83c553f Winbond Electronics Corp America, w83c553f Datasheet - Page 70

• Manufacturer Part Number: w83c553f
• Description: System I/o Controller With Pci Arbiter
• Manufacturer: Winbond Electronics Corp America

W83C553F
Chip Select Control Register (default = 33h)
Type:
Bit Description:
WINBOND SYSTEMS LABORATORY
Bit 7:
Bit 6:
Bit 5:
Bit 4:
Bits [3:2]:
Bit 1:
Bit 0:
Read/Write
EBIOSCSE. Extended BIOS Enable.
LBIOSCSE. Lower BIOS Enable.
BIOSWP. BIOS Write Protect.
UBIOSCSE. Upper BIOS Chip Select Enable. This bit defaults to "1" after reset.
Reserved.
KBCSE. Keyboard Controller Address Location Enable. .
RTCCSE. RTC Address Location Enable.
0=
1=
0=
1=
0=
1=
0=
1=
0=
1=
0=
1=
Disabled
Memory access from FFF80000h to FFFDFFFFh will assert ROMCS in
PowerPC mode or the encoded output XCS[1:0 = 11 in x86 mode.
Disabled
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.
Disabled
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.
Disabled
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..
Disabled
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.
Disabled
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.
Electrical Specifications
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