2 voltage capabilities (addr: 010 000; 10h), 3 voltage readout (addr: 010 001; 11h), 0 register set – Rainbow Electronics LM41 User Manual
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2.0 Register Set
(Continued)
Function Event
The Voltage-Only Measurement function generates a Function Event to the master whenever a conversion
cycle is completed and new data is stored in the Readout register. When the new data is stored into the Readout register the SF2
bit in the Device Status register is set to 1 and remains set, until it is cleared by reading the Readout register. An Attention Request
is generated on the bus, only if it is enabled by the Attention Enable bit (ATE) in the Control register.
Setup Before Enabling
No setup is required for the Voltage-Only Measurement function before it is enabled.
2.10.2 Voltage Capabilities (Addr: 010 000; 10h)
Reg
Add
Register
Name
R/
W
P
O
R
Val
Bit
15
MSb
Bit
14
Bit
13
Bit
12
Bit
11
Bit
10
Bit
9
Bit
8
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
LSb
010 000
Voltage
Capabilities
R 0051h
Reserved
# of Voltage Sensors
Rout
Size
9-bit Resolution
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
1
This register defines the format of the voltage data in the voltage readout register. The LM41 only supports one format for all
voltage measurements as defined by the values of this register.
Bit
Type
Description
2-0
RO
Resolution. This field defines the total number of significant bits in the Voltage Readout field in the Readout
register for this function. The voltage data is always aligned to the left in the Voltage Readout filed and is
extended with zeros.
001: 9-bit (value for the LM41 for other field values see the SensorPath specification)
3
RO
RoutSize (Readout Register size). Defines the total size of the Readout register.
0: 16 bits. (value for the LM41 for other field values see the SensorPath specification)
8-4
RO
# of Voltage Sensors (Number of Voltage Sensors). Specifies the number of Voltage Sensors supported
by this function.
5: The number of Voltage Sensors. (value for the LM41 for other field values see the SensorPath
specification)
15-9
RO
Reserved. Will always read "0".
2.10.3 Voltage Readout (Addr: 010 001; 11h)
Reg
Add
Register
Name
R/
W
P
O
R
Val
Bit
15
MSb
Bit
14
Bit
13
Bit
12
Bit
11
Bit
10
Bit
9
Bit
8
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
LSb
010 001
Voltage
Readout
R
Voltage Readout
Reserved
SNUM
Reserved
MSb
LSb
0
0
0
0
Bit
Type
Description
0-1
RO
Reserved. Will always read "0".
4-2
RO
SNUM (Sensor Number). This field indicates the number of the current Voltage Sensor, to which the data in
the Voltage Readout field belongs. See Table Analog Input Voltage Mapping for assignments.
6-5
RO
Reserved. Will always read "0".
15-7
RO
Voltage Readout. This field holds the result of the voltage measurement. The active size of this field for the
LM41 is 9-bits, left justified. See Table Analog Input Voltage Mapping for voltage mapping details.
LM41
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