EMC6D102-CZC-TR Standard Microsystems (SMSC), EMC6D102-CZC-TR Datasheet - Page 50

• Manufacturer Part Number: EMC6D102-CZC-TR
• Manufacturer: Standard Microsystems (SMSC)

Specifications of EMC6D102-CZC-TR

• Operating Current: 3mA
• Operating Temperature Classification: Commercial
• Package Type: SSOP
• Lead Free Status / Rohs Status: Compliant

Revision 0.4 (09-25-07)
7.2.5
Register
Address
2Ah
2Bh
2Ch
2Dh
2Eh
2Fh
28h
29h
(SENSOR ERROR)
TEMPERATURE
Read/
Write
Registers 28-2Fh: Fan Tachometer Reading
The Fan Tachometer Reading registers contain the number of 11.111μs periods (90KHz) between full
fan revolutions. Fans produce two tachometer pulses per full revolution. These registers are updated
at least once every second.
This value is represented for each fan in a 16 bit, unsigned number.
The Fan Tachometer Reading registers always return an accurate fan tachometer measurement, even
when a fan is disabled or non-functional, including when the start bit=0.
When one byte of a 16-bit register is read, the other byte latches the current value until it is read, in
order to ensure a valid reading. The order is LSB first, MSB second.
FFFFh indicates that the fan is not spinning, or the tachometer input is not connected to a valid signal
(This could be triggered by a counter overflow).
These registers are read only – a write to these registers has no effect.
R
R
R
R
R
R
R
R
-127°c
127°c
-50°c
50°c
0°c
.
.
.
.
.
.
.
.
.
.
.
.
Register Name
Tach1 MSB
Tach2 MSB
Tach3 MSB
Tach4 MSB
Tach1 LSB
Tach2 LSB
Tach3 LSB
Tach4 LSB
Table 7.3 Temperature vs. Register Reading
Fan Control Device with Hardware Monitoring and Acoustic Noise Reduction Features
READING (DEC)
DATASHEET
(MSb)
Bit 7
15
15
15
15
7
7
7
7
-127
127
-50
50
0
.
.
.
.
.
.
.
.
.
.
.
.
50
Bit 6
14
14
14
14
6
6
6
6
Bit 5
13
13
13
13
5
5
5
5
Bit 4
12
12
12
12
4
4
4
4
Bit 3
11
11
11
11
3
3
3
3
Bit 2
READING (HEX)
10
10
10
10
2
2
2
2
CEh
Bit 1
7Fh
81h
00h
32h
80h
1
9
1
9
1
9
1
9
.
.
.
.
.
.
.
.
.
.
.
.
SMSC EMC6D102
(LSb)
Bit 0
0
8
0
8
0
8
0
8
Datasheet
Default
Value
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A