Fan Control Device with Hardware Monitoring and Acoustic Noise Reduction Features
Datasheet
7.2
Defined Registers
7.2.1
Register 10h: SMSC Test Register
Register
Address
Read/
Write
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
(MSb)
(LSb)
10h
R/W
SMSC TEST
TST7
TST6
TST5
TST4
TST3
TST2
TST1
TST0
00h
Setting the Lock bit has no effect on this register.
This register must not be written. Writing this register may produce unexpected results.
7.2.2
Register 1Dh, 1Eh, 1Fh: Offset Registers
Register
Address
Read/
Write
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
(MSb)
(LSb)
1Dh
1Eh
1Fh
R/W
R/W
R/W
Offset Register Ambient
Offset Register 2
7
7
7
6
6
6
5
5
5
4
4
4
3
3
3
2
2
2
1
1
1
0
0
0
00h
00h
00h
Offset Register 1
These registers become read only when the Lock bit is set. Any further attempts to write to these
registers shall have no effect.
Offset Register Ambient only applies to the internal (ambient) temperature reading. This register
contains a 2's complement value, which is added (or subtracted if the number is negative) to the
ambient temperature reading. The default value in the offset register is zero, so initially zero is always
added to the temperature reading.
Offset Register 2 only applies to the remote diode 2 temperature reading. This register contains a
2's complement value, which is added (or subtracted if the number is negative) to external temperature
reading 2. The default value in the offset register is zero, so initially zero is always added to the
temperature reading.
Offset Register 1 only applies to the remote diode 1 temperature reading. This register contains a
2's complement value, which is added (or subtracted if the number is negative) to the external
temperature reading 1 reading. The default value in the offset register is zero, so initially zero is always
added to the temperature reading.
7.2.3
Registers 20-24h: Voltage Reading
Register
Address
Read/
Write
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
(MSb)
(LSb)
20h
21h
22h
23h
24h
R
R
R
R
R
+2.5V Reading
Vccp Reading
VCC Reading
+5V Reading
+12V Reading
7
7
7
7
7
6
6
6
6
6
5
5
5
5
5
4
4
4
4
4
3
3
3
3
3
2
2
2
2
2
1
1
1
1
1
0
0
0
0
0
N/A
N/A
N/A
N/A
N/A
Revision 0.4 (04-05-05)
SMSC EMC6D102
DATA4S8HEET
SMSC [ SMSC CORPORATION ]
