Pci configuration 3 register, Pci clocks of, Being negated. this is the time allowed from – Digi NS9750 User Manual
Page 455

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P C I - t o - A H B B r i d g e
Register bit assignment
PCI Configuration 3 register
Address: A030 001C
The PCI Configuration 3 register contains the values that will be read from the PCI
Max_Lat, PCI Min_Gnt, and PCI Interrupt Pin registers.
Change these fields only during system initialization, when there is no PCI activity. In
a system where NS9750 is not the host, these fields must be programmed within 2
25
PCI clocks of
RST#
being negated. This is the time allowed from
RST#
negated to the
first configuration cycle on the PCI bus.
Register bit assignment
Bits
Access
Mnemonic
Reset
Description
D31:16
R/W
SUBSYSTEM_ID
0x0000
Subsystem ID value
Value to be inserted into the PCI Subsystem ID
register. Defaults to
0x0000
.
D15:00
R/W
SUBVENDOR_ID
0x0000
Subvendor ID value
Value to be inserted into the PCI Subvendor ID
register. Defaults to
0x0000
.
Table 266: PCI Configuration 2 register
Bits
Access
Mnemonic
Reset
Description
D31:24
Read only;
hard-wired to
0
Reserved
N/A
N/A
Table 267: PCI Configuration 3 register
Reserved
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
MIN_GRANT
MAX_LATENCY
INTERRUPT_PIN