11 registers 44-4dh: voltage limit registers, Table 2. voltage limits vs register setting, 12 registers 4e-53h: temperature limit registers – Rainbow Electronics LM85 User Manual
Page 15: Functional description
Functional Description
(Continued)
4.11 Registers 44-4Dh: Voltage Limit Registers
Register
Address
Read/
Write
Register
Name
Bit 7
(MSB)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(LSB)
Default
Value
44h
R/W
2.5V Low Limit
7
6
5
4
3
2
1
0
00h
45h
R/W
2.5V High Limit
7
6
5
4
3
2
1
0
FFh
46h
R/W
V
CCP
Low Limit
7
6
5
4
3
2
1
0
00h
47h
R/W
V
CCP
High Limit
7
6
5
4
3
2
1
0
FFh
48h
R/W
3.3V Low Limit
7
6
5
4
3
2
1
0
00h
49h
R/W
3.3V High Limit
7
6
5
4
3
2
1
0
FFh
4Ah
R/W
5V Low Limit
7
6
5
4
3
2
1
0
00h
4Bh
R/W
5V High Limit
7
6
5
4
3
2
1
0
FFh
4Ch
R/W
12V Low Limit
7
6
5
4
3
2
1
0
00h
4Dh
R/W
12V High Limit
7
6
5
4
3
2
1
0
FFh
If a voltage input either exceeds the value set in the voltage high limit register or falls below the value set in the voltage low limit
register, the corresponding bit will be set automatically by the LM85 in the interrupt status registers (41-42h). Voltages are
presented in the registers at
3
⁄
4
full scale for the nominal voltage, meaning that at nominal voltage, each input will be C0h, as
shown in Table 2.
Setting the Ready/Lock/Start/Override register Lock bit has no effect on these registers.
TABLE 2. Voltage Limits vs Register Setting
Input
Nominal
Voltage
Register Setting at
Nominal Voltage
Maximum
Voltage
Register Reading at
Maximum Voltage
Minimum
Voltage
Register Reading at
Minimum Voltage
2.5V
2.5V
C0h
3.32V
FFh
0V
00h
V
CCP
2.25V
C0h
3.00V
FFh
0V
00h
3.3V
3.3V
C0h
4.38V
FFh
3.0V
AFh
5V
5.0V
C0h
6.64V
FFh
0V
00h
12V
12.0V
C0h
16.00V
FFh
0V
00h
4.12 Registers 4E-53h: Temperature Limit Registers
Register
Address
Read/
Write
Register
Name
Bit 7
(MSB)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(LSB)
Default
Value
4Eh
R/W
Processor (Zone1)
Low Temp
7
6
5
4
3
2
1
0
81h
4Fh
R/W
Processor (Zone1)
High Temp
7
6
5
4
3
2
1
0
7Fh
50h
R/W
Processor (Zone2)
Low Temp
7
6
5
4
3
2
1
0
81h
51h
R/W
Processor (Zone2)
High Temp
7
6
5
4
3
2
1
0
7Fh
52h
R/W
Processor (Zone3)
Low Temp
7
6
5
4
3
2
1
0
81h
53h
R/W
Processor (Zone3)
High Temp
7
6
5
4
3
2
1
0
7Fh
If an external temperature input or the internal temperature sensor either exceeds the value set in the corresponding high limit
register or falls below the value set in the corresponding low limit register, the corresponding bit will be set automatically by the
LM85 in the Interrupt Status Register 1 (41h). For example, if the temperature read from the Remote1− and Remote1+ inputs
exceeds the Processor (Zone1) High Temp register limit setting, Interrupt Status Register 1 ZN1 bit will be set. The temperature
limits in these registers are represented as 8 bit, 2’s complement, signed numbers in Celsius, as shown below in Table 3.
Setting the Ready/Lock/Start/Override register Lock bit has no effect on these registers.
LM85
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