Vaisala CARBOCAP GMP231, Руководство пользователя

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Message bytes (hex) Sent by Content
00 GMP231 Status byte (no errors, ACK)
81 Get_parameter command
09 Device address
0B Frame length
0A CO
2
Parameter ID
69 CO
2
value 653.6314 ppm
68
23
44
75 CRC high
7D CRC lo
Master
I
2
C end condition
5.2.3 Set_Parameter
Set_Parameter command (ID 82
hex
) writes parameter values to non-volatile memory. You can
use it to set the operational parameters of the GMP231. Depending on the change, the
functionality of the GMP231 may not change immediately.
The length of the invoke message varies depending on the data length. The master must write
as many bytes as indicated in the frame length of the invoke message. If the master tries to
write a longer or shorter message, GMP231 rejects the message.
Table 55 Set_Parameter invoke message
Message segment Length Content
I
2
C address
1 byte
I
2
C address (write)
Command ID 1 byte Always 82
hex
Device address 1 byte See Table 46 (page 51) .
Frame length 1 byte Varies according to data length, 07
hex
... 38
hex
.
Data 1 byte Parameter ID
1 ... 50 bytes Parameter value
Checksum 2 bytes See Checksum (page 52) .
Chapter 5 – I2C interface
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