Vaisala GMP231 - Manual (Page 66)

User's Guide _______________________________________________________________________
64 ___________________________________________________________________ M211501EN-C
Adjust
Adjust command (ID 84h) controls the user adjustment sequence of CO
2
measurement.
Table 34 Adjust Invoke Message
Message Segment Length Content
I
2
C address 1 byte I
2
C address (write)
Command ID 1 byte Always 84h
Device address 1 byte See Table 13 on page 51
Frame length 1 byte Varies according to data length,
07h ... 0Bh.
Data 1 byte Adjustment subcommand.
See Table 36 below.
1 byte Parameter to be adjusted.
See Table 37 below.
4 bytes Value of parameter. Used only with
subcommands 2 and 3.
Checksum 2 bytes See section Checksum on page 56
Table 35
Adjust Response Message
Message Segment Length Content
I
2
C address 1 byte I
2
C address (read)
Status 1 byte See section Status Byte on page 56.
Command ID 1 byte Always 84h
Device address 1 byte See Table 13 on page 51
Frame length 1 byte Always 07h.
Data 1 byte Return code. See Table 38 on page 65.
Checksum 2 bytes See section Checksum on page 56.
Table 36
Adjustment Subcommands
Code Adjustment operation
0
Start 1 point adjustment
1 Start 2 point adjustment
2 Record measured point 1, reference value is given in parameter
3 Record measured point 2, reference value is given in parameter
4 Cancel adjustment (previous adjustment is reverted)
5 End (adjustment is saved and new values are taken in use)
6 Revert to factory calibration (clear user adjustment)
Table 37
Adjustment Parameters
Code Purpose
0
All parameters (valid with revert to factory calibration)
1 CO2