Rainbow Electronics LM99 - Manual (Page 15)

2.0 LM99 Registers
(Continued)
Command Select Address Power On Default State Register
Name
Register Function
Read Address
< P7:P0 > hex
Write Address
< P7:P0 > hex
< D7:D0 > binary < D7:D0 >
decimal
10h NA 0000 0000 0 RTLB Remote Temperature Low Byte
11h 11h 0000 0000 0 RTOHB Remote Temperature Offset
High Byte
12h 12h 0000 0000 0 RTOLB Remote Temperature Offset
Low Byte
13h 13h 0000 0000 0 RHSLB Remote HIGH Setpoint Low
Byte
14h 14h 0000 0000 0 RLSLB Remote LOW Setpoint Low
Byte
19h 19h 0110 1110 110 RCS Remote T_CRIT Setpoint
20h 20h 0101 0101 85 LCS Local T_CRIT Setpoint
21h 21h 0000 1010 10 TH T_CRIT Hysteresis
B0h-BEh B0h-BEh Manufacturers Test Registers
BFh BFh 0000 0000 0 RDTF Remote Diode Temperature
Filter
FEh NA 0000 0001 1 RMID Read Manufacturer’s ID
FFh NA LM99 0011 0001
LM99-1 0011 0100
49
52
RDR Read Stepping or Die Revision
Code
2.2 LOCAL and REMOTE TEMPERATURE REGISTERS (LT, RTHB, RTLB)
(Read Only Address 00h, 01h):
BIT D7 D6 D5 D4 D3 D2 D1 D0
Value SIGN 64 32 16 8 4 2 1
For LT and RTHB D7–D0: Temperature Data. LSB = 1˚C. Two’s complement format.
(Read Only Address 10h):
BIT D7 D6 D5 D4 D3 D2 D1 D0
Value 0.5 0.25 0.125 0 0 0 0 0
For RTLB D7–D5: Temperature Data. LSB = 0.125˚C. Two’s complement format.
The maximum value available from the Local Temperature register is 127; the minimum value available from the Local
Temperature register is -128. The maximum value available from the Remote Temperature register is 127.875; the minimum value
available from the Remote Temperature registers is −128.875.
Note that the remote diode junction temperature is actually 16˚C higher than the Remote Temperature Register value.
2.3 STATUS REGISTER (SR)
(Read Only Address 02h):
D7 D6 D5 D4 D3 D2 D1 D0
Busy LHIGH LLOW RHIGH RLOW OPEN RCRIT LCRIT
Power up default is with all bits “0” (zero).
D0: LCRIT: When set to “1” indicates a Local Critical Temperature alarm.
D1: RCRIT: When set to “1” indicates a Remote Diode Critical Temperature alarm.
D2: OPEN: When set to “1” indicates a Remote Diode disconnect.
D3: RLOW: When set to “1” indicates a Remote Diode LOW Temperature alarm
D4: RHIGH: When set to “1” indicates a Remote Diode HIGH Temperature alarm.
D5: LLOW: When set to “1” indicates a Local LOW Temperature alarm.
D6: LHIGH: When set to “1” indicates a Local HIGH Temperature alarm.
D7: Busy: When set to “1” ADC is busy converting.
LM99
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