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248
Revision 1.1
G
Core Logic Module
(Continued)
I/O Base Address Register (Bit 0 = 1)
31:2
Address Mask.
Determines the size of the BAR.
— Every bit that is a 1 is programmable in the BAR.
— Every bit that is a 0 is fixed 0 in the BAR.
Since the address mask goes down to bit 2, the smallest I/O region is 4 bytes, however, the PCI Specification suggests not
using less than a 4 KB address range.
Reserved.
Must be set to 0.
This bit must be set to 1, to indicate an I/O base address register.
1
0
Index 44h-47h
To use F5BAR1, the mask register should be programmed first. The mask register defines the size of F5BAR1 and whether the
accessed offset registers are memory or I/O mapped. See F5 Index 40h (F5BAR0 Mask Address Register) above for bit descriptions.
Note:
Whenever a value is written to this mask register, F5BAR1 must also be written (even if the value for F5BAR1 has not
changed).
F5BAR1 Mask Address Register (R/W)
Reset Value: 00000000h
Index 48h-4Bh
To use F5BAR2, the mask register should be programmed first. The mask register defines the size of F5BAR2 and whether the
accessed offset registers are memory or I/O mapped. See F5 Index 40h (F5BAR0 Mask Address Register) above for bit descriptions.
Note:
Whenever a value is written to this mask register, F5BAR2 must also be written (even if the value for F5BAR2 has not
changed).
F5BAR2 Mask Address Register (R/W)
Reset Value: 00000000h
Index 4Ch-4Fh
To use F5BAR3, the mask register should be programmed first. The mask register defines the size of F5BAR3 and whether the
accessed offset registers are memory or I/O mapped. See F5 Index 40h (F5BAR0 Mask Address Register) above for bit descriptions.
Note:
Whenever a value is written to this mask register, F5BAR3 must also be written (even if the value for F5BAR3 has not
changed).
F5BAR3 Mask Address Register (R/W)
Reset Value: 00000000h
Index 50h-53h
To use F5BAR4, the mask register should be programmed first. The mask register defines the size of F5BAR4 and whether the
accessed offset registers are memory or I/O mapped. See F5 Index 40h (F5BAR0 Mask Address Register) above for bit descriptions.
Note:
Whenever a value is written to this mask register, F5BAR4 must also be written (even if the value for F5BAR4 has not
changed).
F5BAR4 Mask Address Register (R/W)
Reset Value: 00000000h
31:4
3
2:1
0
Address Mask.
Bits [31:24] must be set to FFh. Other bits should be set according to the specific system configuration.
Prefetchable.
Should be set according to the specific system configuration.
Type.
Should be set according to the specific system configuration.
Memory Space Indicator.
Must be set to 0.
Index 54h-57h
To use F5BAR5, the mask register should be programmed first. The mask register defines the size of F5BAR5 and whether the
accessed offset registers are memory or I/O mapped. See F5 Index 40h (F5BAR0 Mask Address Register) above for bit descriptions.
Note:
Whenever a value is written to this mask register, F5BAR5 must also be written (even if the value for F5BAR5 has not
changed).
F5BAR5 Mask Address Register (R/W)
Reset Value: 00000000h
31:4
3
2:1
0
Address Mask.
Bits [31:24] must be set to FFh. Other bits should be set according to the specific system configuration.
Prefetchable.
Should be set according to the specific system configuration.
Type.
Should be set according to the specific system configuration.
Memory Space Indicator.
Must be set to 0.
Table 5-39. F5: PCI Header Registers for X-Bus Expansion (Continued)
Bit
Description