Polling with crc – Vaisala WMT52 User Manual

Page 71

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Chapter 7 __________________________________________________ Getting the Data Messages

VAISALA_______________________________________________________________________ 69

Polling with CRC

Use the same data query commands as in the previous sections but type
the first letter of the command in lower case and add a correct three-
character CRC before the command terminator. The response contains
also a CRC. For more information about the CRC-computation see

Appendix C, CRC-16 Computation, on page 133

.

Requesting a wind data message with a CRC:

Command format: ar1xxx<cr><lf>

Example of the response (the parameter set is configurable):

0r1,Dn=236D,Dm=283D,Dx=031D,Sn=0.0M,Sm=1.0M,Sx=2.2MLFj
<cr><lf>

where the three characters before <cr><lf> are the CRC for the
response.

Example of asking the CRC for the wind data message query ar1:

Command format: ar1yyy<cr><lf>

where
a

=

Device address

r1

=

Wind message query command

xxx

=

Three-character CRC for ar1 command

<cr><lf>

=

Command terminator

NOTE

The correct CRC for each command can be requested by typing the
command with an arbitrary three-character CRC.

where
a

=

Device address

r1

=

Wind message query command

yyy

=

Arbitrary three-character CRC

<cr><lf>

=

Command terminator

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