Rainbow Electronics LM87 - Manual (Page 29)

Functional Description
(Continued)
Bit Name Read Only Description
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.
13.16 Interrupt Status Register 2 Mirror — Address 4Dh
Power on default – < 7:0 > = 0000 0000 binary
Bit Name Read Only Description
0 +12Vin Read Only A one indicates a High or Low limit has been exceeded.
1 Vccp2 Read Only A one indicates a High or Low limit has been exceeded.
2 Reserved Read Only
3 Reserved Read Only
4 CI Read Only A one indicates the CI (Chassis Intrusion) input has gone high.
5 THERM# Read Only A one indicates the THERM# input has been pulled low by external circuitry.
6 D1 Fault Read Only A one indicates the D1 inputs are shorted to Vcc or open circuit.
7 D2 Fault Read Only A one indicates the D2 inputs are shorted to Vcc or open circuit.
13.17 SMBALERT# Enable — Address 80h
Power on default – < 7:0 > = 0010 0000 binary
Bit Name Read/Write Description
0 Reserved Read Only
1 Reserved Read Only
2 Reserved Read Only
3 Reserved Read Only
4 Reserved Read Only
5 Reserved Read Only
6 SMBALERT#
Enable
Read/Write A one enables the SMBALERT# mode of operation.
7 Reserved Read Only
13.18 Value RAM — Address 19h–3Fh
Address A6–A0 Description
19h DAC data register; power on default < 7:0 > =1111 1111 binary
1Ah AIN1 Low Limit
1Bh AIN2 Low Limit
20h +2.5V/External Temperature 2 reading
21h Vccp1 reading
22h +Vcc reading
23h +5V reading
24h +12V reading
25h Vccp2 reading
26h External Temperature 1 reading
27h Internal Temperature reading
28h FAN1/AIN1 reading
Note: For the FAN reading, this location stores the number of counts of the internal clock per
revolution.
29h FAN2/AIN2 reading
Note: For the FAN reading, this location stores the number of counts of the internal clock per
revolution.
LM87
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