ADT7473 Analog Devices, Inc., ADT7473 Datasheet - Page 73

• Manufacturer Part Number: ADT7473
• Description: Dbcool Remote Thermal Monitor And Fan Controller
• Manufacturer: Analog Devices, Inc.

Table 54. Register 0x79— THERM Timer Status Register (Power-On Default = 0x00)
Bit
[7:1]
[0]
Table 55. Register 0x7A— THERM Timer Limit Register (Power-On Default = 0x00)
Bit
[7:0]
Table 56. Register 0x7B—TACH Pulses per Revolution Register (Power-On Default = 0x55)
Bit
[1:0]
[3:2]
[5:4]
[7:6]
Name
LIMT
Name
FAN1
FAN2
FAN3
FAN4
Name
TMR
ASRT/
TMR0
R/W
Read-only
Read-only
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Description
Times the duration THERM input is asserted. These seven bits read 0 until the THERM assertion time
exceeds 45.52 ms.
This bit is set high on the assertion of the THERM input, and is cleared on read. If the THERM assertion time
exceeds 45.52 ms, this bit is set and becomes the LSB of the 8-bit TMR reading. This allows THERM assertion
times from 45.52 ms to 5.82 seconds to be reported back with a resolution of 22.76 ms.
Description
Sets maximum THERM assertion length allowed before an interrupt is generated. This is an 8-bit
limit with a resolution of 22.76 ms allowing THERM assertion limits of 45.52 ms to 5.82 seconds to
be programmed. If the THERM assertion time exceeds this limit, Bit 5 (F4P) of Interrupt Status
Register 2 (Reg. 0x42) is set. If the limit value is 0x00, an interrupt is generated immediately on the
assertion of the THERM input.
Description
Sets number of pulses to be counted when measuring Fan 1 speed. Can be used to determine fan
pulses per revolution for unknown fan type.
Pulses Counted
00 = 1
01 = 2 (default)
10 = 3
11 = 4
Sets number of pulses to be counted when measuring Fan 2 speed. Can be used to determine fan
pulses per revolution for unknown fan type.
Pulses Counted
00 = 1
01 = 2 (default)
10 = 3
11 = 4
Sets number of pulses to be counted when measuring Fan 3 speed. Can be used to determine fan
pulses per revolution for unknown fan type.
Pulses Counted
00 = 1
01 = 2 (default)
10 = 3
11 = 4
Sets number of pulses to be counted when measuring Fan 4 speed. Can be used to determine fan
pulses per revolution for unknown fan type.
Pulses Counted
00 = 1
01 = 2 (default)
10 = 3
11 = 4
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ADT7473