Rainbow Electronics LM81 - Manual (Page 30)

Functional Description
(Continued)
13.14 Extended Mode Register 1 — Address 4Ch
Power on default – < 7:0 > = 0100 0100 binary
Bit Name Read/Write Description
0 Extended Mode
Enable Read/Write A one enables the Extended Interrupt Modes, the T_CRIT_A output and all the
functions listed in the Extended Mode Registers. Bit 7 of the Interrupt Status
register will be activated to reflect the interrupt status of the LOW limit comparison
result.
1 LOW Limit Mask
Bit Read/Write A mask bit for the LOW limit Interrupt. A one disables the interrupt from propagating
to the INT pin.
2-3 T_CRIT_A
Interrupt Mode
Select Read/Write The state of these bits select the interrupt mode for T_CRIT_A as described below.
< 3:2 > = 00 or < 3:2 > = 11: Repetitive Interrupt Mode
< 3:2 > = 01: One-Time Interrupt Mode
< 3:2 > = 10: Comparator Mode
4 T_CRIT_A
Enable Read/Write A one enables the T_CRIT_A pin.
5 T_CRIT_A
Polarity Read/Write A one sets the T_CRIT_A pin active HIGH. A zero sets the T_CRIT_A pin active
LOW.
6 T_CRIT_A Mask
Enable Read/Write A one prevents the T_CRIT_A interrupt from propagating to the INT output pin.
7 T_CRIT_A Status
Bit Read A one indicates that a T_CRIT_A interrupt has occurred.
13.15 Extended Mode Register 2 — Address 4Dh
Power on default – < 7:0 > = 0000 0000 binary
Bit Name Read/Write Description
0-2 Hysteresis Offset
Value Read/Write T
HYST
value.
3 12-bit
Temperature
Resolution Enable Read/Write A one sets the temperature resolution to 12 bits.
4-7 12-bit
Temperature Data Read Only 12-bit temperature data least significant bits. Bit 7 mirrors bit 7 in the temperature
configuration register (4Bh) and has a weight of 0.5˚C; bits 6-4 have a weight of
0.25, 0.125, and 0.0625˚C, respectively.
LM81
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