HP Compaq d330 DT Technical Reference Manual page 58

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>. 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
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 funct
bits <10..8>) is used to elect a particul
Register 0CF8h
Results in:
AD31..0
(w/Type 00
Con fig. Cycle)
NOTES:
[1] Bits <1,0> : 00 = Type 0 Cycle, 01 = Type 1 cycle
Type 01 cycle only. Reserv
Figure 4-2. Configuration Cycle
Table 4-1 shows the standard configuration of device num
components and slots residing on a PCI bus.
Table 4-1. PCI Device Conf
PCI Component
82865G GMCH:
Memory Controller
AGP Bri dge
Integrated Gra
AGP slot
82801EB ICH5
PCI Bridge
LPC Bridge
EIDE Controller
Serial ATA Controller
SMBus Cont roller
USB I/F #1
USB I/F #2
USB I/F #3
USB I/F #4
USB 2.0 Controller
AC97 Audio Controller
AC97 Modem Controlle
Network Interface Cont
PCI Connector 1 (slot 1)
PCI Connector 2 (slot 2)
PCI Connector 3 (slot 3)
PCI Connector 4 (slot 4)
PCI Con nector 5 (slot 5)
N OTES:
[1] ST, SFF, DT, MT, & CM
[2] S T, DT, MT, & CMT form factors only.
[3] CMT form factor only.
4-4 hp compaq d330 and d530 Series of Personal Computers
Featuring the Intel Pentium 4 Processor
s ar fu
3
2 2
Reserved
IDSEL (only one signal line asserted)
ed on Type 00 cycle.
iguration Access
PCI C ompon
Notes
phics Controller
r
roller
[1]
[2]
[3]
[3]
T form factors only.
First Edition – June 2003
nction wit n a PCI hi co ponent m
1 1 1 1
Bus Device Function
Number Number Number
Function
Number
bers and IDSEL connections for
Table 4-1.
ent Configurat ion Ac cess
Function # Dev
0
0
0
0
0
0
1
2
3
0
1
2
3
7
5
6
0
0
0
0
0
0
or it
ion number (CF8h,
.
8 7 2 1 0 [1]
Register
Index
Register
Index
PCI IDSEL
ice # Bus # Wired to:
--
0
0
1
0
2
0
0 1 --
--
30 0
31 0
31
0
31
0
31
0
29
0
29
0
29
0
29
0
29
0
31
0
31
0
8
5
4 5 AD20
9 5 AD25
10 5 AD26
11 5 AD27
13 5 AD29
>