W83783S Information Storage Devices, Inc, W83783S Datasheet - Page 11

• Manufacturer Part Number: W83783S
• Description: H/w Monitor: 3 Temp.(thermal Diode), 6 Vol., 2 PWM Fan Control
• Manufacturer: Information Storage Devices, Inc

6. FUNCTIONAL DESCRIPTION
6.1 General Description
The W83783S provides at most 6 analog positive inputs, 3 fan speed monitors, 2 sets for fan PWM
(Pulse Width Modulation) control, 2 thermal inputs from remote thermistors or 2N3904 transistors or
Pentium
exceed the set limit value including voltage, temperature, or fan counter. When start the monitor
function on the chip, the watch dog machine monitor every function and store the value to registers. If
the monitor value exceeds the limit value, the interrupt status will be set to 1.
6.2 Access Interface
The W83783S provides I
serial bus address. The first address defined at CR[48h] can read/write all registers excluding Bank 1
temperature sensor registers and the address default value is 0101101. The second address defined
at CR[4Ah] bit2-0 only read/write temperature sensor 1 registers and the address default value is
1001001.
6.2.1 The first serial bus access timing are shown as follow:
(a) Serial bus write to internal address register followed by the data byte
SCL
SDA
TM
II (Deschutes) thermal diode outputs and beep function output when the monitor value
Start By
Master
0
0
Figure 1. Serial Bus Write to Internal Address Register followed by the Data Byte
1
Serial Bus Address Byte
2
C Serial Bus to read/write internal reigsters. In the W83783S there are two
0
SCL
SDA (Continued)
Frame 1
1
(Continued)
1
0
1
- 6 -
R/W
0
D7
7
Ack
781D
by
8
D6
0
D7
D5
D6
D4
Internal Index Register Byte
D5
D3
Data Byte
Frame 3
Frame 2
Publication Release Date: April 1999
D4
D2
D3
D1
D2
7
D0
Ack
781D
by
D1
8
7
D0
Master
Stop
by
W83783S
Preliminary
Ack
781D
by
8
Revision 0.55