Software Functional Overview 3-13
SMBus Devices
The SMBus is a two-wire interface through which the system can communicate
with power-related chips. The BIOS should initialize the SMBus devices during
POST.
SMBus Devices
SMBus Device
Host/Slave
Address
BIOS Need to Initialization
PIIX4 – Core Logic
Both Host and Slave
10h
Enable SMBus interface and
SMBus interrupt
PIC16C62 – micro P
Both Host and Slave
04h
No need
MAXIM 1617 –
Temperature Sensor
Slave
9Ch
Program the desired
temperature range:
(Tos=48°C, Thyst= 52°C)
IMISC671 – Clock
Synthesizer
Slave
D2h
Program the desired clock
frequency (Pin23 output 24
MHz, Pin22 output 48 MHz)
BQ2092 – Smart Battery
Both Host and Slave
16h
No need
Resource Allocation
The following tables describe the resource allocations.
Device Addresses
Hex Address
Device
000-01F
8237-1
020-021
8259-1
022
430TX control Register
040-05F
8254
060-06F
Keyboard Controller
070-07F
RTC & NMI Mask
080-08F
DMA Page Registers
092
System Control Port
0A0-0A1
8259-2
0C0-0DF
8237-2
0F0-0FF
Math Coprocessor
170-177
Secondary IDE Controller
1F0-1F7
Primary IDE Controller
200-20F
Game Port
220-22F
Sound Blaster
279
PnP configuration – Address Port
2F8-2FF
FIR
