Rainbow Electronics LM87 - Manual (Page 26)

Functional Description
(Continued)
13.5 Configuration Register 1 — Address 40h
Power on default – < 7:0 > = 00001000 binary
Bit Name Read/Write Description
0 Start Read/Write A one enables startup of monitoring operations, a zero puts the part in standby mode.
Note: The outputs of Interrupt pins will not be cleared if the user writes a zero to this
location after an interrupt has occurred, unlike the “INT_Clear” bit.
At start up, limit checking functions and scanning begin. Note, all limits should be set in
the Value RAM before setting this bit HIGH.
1 INT# Enable Read/Write A one enables the INT# Interrupt output.
2 THERM#
Enable
Read/Write A one enables the THERM# Interrupt output.
3 INT#_Clear Read/Write A one disables the INT# output without affecting the contents of Interrupt Status
Registers. The device will stop monitoring. It will resume upon clearing of this bit.
4 RESET# Read/Write A one outputs a 20 ms minimum active low reset signal at RESET#. This bit is cleared
once the pulse has gone inactive.
5 Reserved Read/Write
6 THERM#_Clear Read/Write A one disables the THERM# output without affecting the contents of Interrupt Status
Registers.
7 INITIALIZATION Read/Write A one restores power on default values to the Configuration Register, Interrupt Status
Registers, Interrupt Mask Registers, CI Clear Register, VID/Fan Divisor Register, VID4,
Temperature Configuration Register, and the Extended Mode Registers. This bit clears
itself since the power on default is zero.
13.6 Interrupt Status Register 1 — Address 41h
Power on default – < 7:0 > = 0000 0000 binary
Bit Name Read/Write Description
0 +2.5Vin Read Only A one indicates a High or Low limit has been exceeded.
1 Vccp1 Read Only A one indicates a High or Low limit has been exceeded.
2 Vcc Read Only A one indicates a High or Low limit has been exceeded.
3 +5Vin Read Only A one indicates a High or Low limit has been exceeded.
4 Int. Temp. Read Only A one indicates a High or Low limit has been exceeded.
5 Ext. Temp. Read Only A one indicates a High or Low limit has been exceeded.
6 FAN1/AIN1 Read Only A one indicates the fan count limit has been exceeded or an AIN1 High or Low limit has
been exceeded.
7 FAN2/AIN2 Read Only A one indicates the fan count limit has been exceeded or an AIN2 High or Low limit has
been exceeded.
LM87
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