W83627HF/ F/ HG/ G
7. HARDWARE MONITOR
7.1 General Description
The W83627HF can be used to monitor several critical hardware parameters of the system, including
power supply voltages, fan speeds, and temperatures, which are very important for a high-end com-
puter system to work stable and properly. W83627HF provides both LPC and I2CTM serial bus inter-
face to access hardware.
An 8-bit analog-to-digital converter（ADC）was built inside W83627HF. The W83627HF can simulta-
neously monitor 9 analog voltage inputs, 3 fan tachometer inputs, 3 remote temperature, one case-
open detection signal. The remote temperature sensing can be performed by thermistors, or 2N3904
NPN-type transistors, or directly from IntelTM Deschutes CPU thermal diode output. Also the
W83627HF provides： 2 PWM（pulse width modulation）outputs for the fan speed control; beep tone
output for warning; SMI#（through serial IRQ）, OVT#, GPO# signals for system protection events.
Through the application software or BIOS, the users can read all the monitored parameters of system
from time to time. And a pop-up warning can be also activated when the monitored item was out of
the proper/preset range. The application software could be Winbond's Hardware DoctorTM, or IntelTM
LDCM （LanDesk Client Management）, or other management application software. Also the users
can set up the upper and lower limits （alarm thresholds） of these monitored parameters and to ac-
tivate one programmable and maskable interrupts. An optional beep tone could be used as warning
signal when the monitored parameters are out of the preset range.
Additionally, 5 VID inputs are provided to read the VID of CPU （i.e. PentiumTM II） if applicable. This
is to provide the Vcore voltage correction automatically. Also W83627HF uniquely provides an op-
tional feature： early stage （before BIOS was loaded） beep warning. This is to detect if the fatal
elements present --- Vcore or +3.3V voltage fail, and the system can not be boomed up.
7.2
Access Interface
The W83627HF provides two interface for microprocessor to read/write hardware monitor internal reg-
isters.
7.2.1 LPC interface
The first interface uses LPC Bus to access which the ports of low byte （bit2~bit0） are defined in the
port 5h and 6h. The other higher bits of these ports is set by W83627HF itself. The general decoded
address is set to port 295h and port 296h. These two ports are described as following：
Port 295h： Index port.
Port 296h： Data port.
The register structure is showed as the Figure 8.1
Publication Release Date: June 09, 2006
- 27 -
Revision 2.27
WINBOND [ WINBOND ]
