Vaisala CARBOCAP GMP231, User Manual

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Message segment Length Content
Frame length 1 byte Always 05
hex
Checksum 2 bytes See Checksum (page 52) .
Table 51 Get_Interface_Version response message
Message segment Length Content
I
2
C address
1 byte
I
2
C address (read)
Status 1 byte See Status byte (page 51) .
Command ID 1 byte Always 80
hex
Device address 1 byte See Table 46 (page 51) .
Frame length 1 byte Always 0A
hex
Data 1 byte Device version
1 byte Protocol frame version
1 byte Command set version
1 byte Parameter set version
Checksum 2 bytes See Checksum (page 52) .
5.2.2 Get_Parameter
Get_Parameter command (ID 81
hex
) reads parameter values. You can use it to read both
measurement results and operational parameters. If the master tries to read more bytes than
message size, the slave sends FF
hex
bytes.
Table 52 Get_Parameter invoke message
Message segment Length Content
I
2
C address
1 byte
I
2
C address (write)
Command ID 1 byte Always 81
hex
Device address 1 byte See Table 46 (page 51) .
Frame length 1 byte Always 06
hex
Data 1 byte ID of parameter to be read
Checksum 2 bytes See Checksum (page 52) .
Chapter 5 – I2C interface
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