Download Compaq Evo Workstation w4000 - Convertible Minitower Specifications

Technical Reference Guide
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>. With three or more PCI buses, a PCI bridge
may convert a Type 1 to a Type 0 if it’s destined for a device being serviced by that bridge or it
may forward the Type 1 cycle unmodified if it is destined for a device being serviced by a
downstream bridge. 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.
3
Register 0CF8h
2 2
Reserved
1 1
1 1
8 7
2 1 0 [1]
Bus
Device
Function
Register
Number
Number
Number
Index
Results in:
AD31..0
(w/Type 00
Config. Cycle)
IDSEL (only one signal line asserted)
Function
Number
Register
Index
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
Table 4-1.
PCI Component Configuration Access
PCI Component
Notes
Function #
82845 MCH:
0
Memory Controller
0
AGP Bridge
AGP slot
0
82801BA ICH2:
0
PCI Bridge
0
LPC Bridge
1
EIDE Controller
2
USB I/F #1
3
SMBus Controller
4
USB I/F #2
5
AC97 Audio Controller
6
[1]
AC97 Modem Controller
0
Network Interface Controller
PCI Connector 1 (slot 1)
[2]
0
PCI Connector 2 (slot 2)
[2]
0
PCI Connector 3 (slot 3)
[2, 3]
0
PCI Connector 4 (slot 4)
[2, 4]
0
PCI Connector 5 (slot 5)
[2, 4]
0
NOTES:
[1] Not implemented.
[2] PCI bus number given is for standard configuration.
[3] Desktop and Configurable Minitower models only.
[4] Configurable minitower models only.
Device #
PCI
Bus #
0 (00h)
1 (01h)
0 (00h)
0
0
1
30 (1Eh)
31 (1Fh)
31 (1Fh)
31 (1Fh)
31 (1Fh)
31 (1Fh)
31 (1Fh)
31 (1Fh)
8 (08h)
4 (04h)
9 (09h)
10 (0Ah)
11 (0Bh)
13 (0Dh)
0
0
0
0
0
0
0
0
2
2
2
2
2
2
IDSEL
Wired to:
----
AD20
AD25
AD26
AD27
AD29
Compaq Evo and Workstation Personal Computers 4-5
Featuring the Intel Pentium 4 Processor
Second Edition - January 2003