HP Compaq D315 Technical Reference Manual page 54

Chapter 4 System Support
Two types of configuration cycles are used. A Type 0 (zero) cycle is targeted to a device on the
PCI bus on which the cycle is running. A Type 1 cycle is targeted to a device on a downstream
PCI bus as identified by bus number bits <23..16>. Figure 4-2 shows the configuration cycle
format and how the loading of 0CF8h results in a Type 0 configuration cycle on the PCI bus. The
Device Number (bits <15..11> determines which one of the AD31..11 lines is to be asserted high
for the IDSEL signal, which acts as a "chip select" function for the PCI device to be configured.
The function number (CF8h, bits <10..8>) is used to select a particular function within a PCI
component.
Register 0CF8h
Results in:
AD31..0
(w/Type 00
Config. Cycle)
NOTES:
[1] Bits <1,0> : 00 = Type 0 Cycle, 01 = Type 1 cycle
Type 01 cycle only. Reserved on Type 00 cycle.
Figure 4-2. Configuration Cycle
Table 4-1 shows the standard configuration of device numbers and IDSEL connections for
components and slots residing on a PCI bus.
Table 4-1. PCI Device Configuration Access
PCI Component: Function
IGP:
CPU Host Bridge
Memory Configuration
Memory Addr. Trans. Cntrl.
Miscellaneous Control
AGP Host
Graphics processing unit [1]
AGP slot
MCP:
Legacy LPC Bridge Control
SMBus Control
USB Controller A
USB Controller B
USB 2.0 Controller
Network interface
Audio processor
Audio Codec
Modem Codec (not used)
PCI-PCI Bridge
IDE Controller
PCI Connector 1 (slot 1)
PCI Connector 2 (slot 2)
PCI Connector 3 (slot 3)
NOTES:
All numbers are in decimal unless otherwise indicated.
Vender ID for all functions is 10DEh.
[1] Will not be "visible" to software if an AGP card is installed in the AGP slot.
[2] Not used in this systems.
[3] Determined by installed device.
[4] D315 / d325
Compaq D315 and hp d325 Personal Computers
4-4
Featuring the AMD Athlon XP Processor
31 24 23
Bus
Reserved
Number
IDSEL (only one signal line asserted)
Table 4-1.
PCI Component Configuration Access
PCI
Bus # Device #
0 0
0 0
0 0
0 0
0 30
1 0
1 0
0 1
0 1
0 2
0 2
0 2
0 4
5
0 6
0 6
0 8
0 9
2 6 / 4
2 7 / 9
2 8 / 10
Second Edition – April 2003
16 15 11 10 8 7
Device Function
Number Number
Function
Number
Function # Device ID [4]
0 01A4h / 01E0h
1 01Ach / 01EBh
2 01ADh / 01EEh
3 01AAh / 01EDh
0 01B7h / 01E8h
0 01A0h / 01F0h
0 [3]
0 01B2h / 0060h
1 01B4h / 0064h
0 01C2h / 0067h
1 01C2h / 0067h
2 na / 0068h
0 [2] / 0066h
0 [2] / [2]
1 01B1h / 006Ah
0 01C1h / 0069h
0 01B8h / 006Ch
01BCh / 006Dh
[3] [3]
[3] [3]
[3] [3]
2 1 0 [1]
Register
Index
Register
Index
IDSEL
Wired to: [4]
n/a
n/a
n/a
AD22 / AD20
AD23 / AD25
AD24 / AD26