Campbell Scientific PWS100 Present Weather Sensor - Manual (Page 65)

Section 7. Operation
FIGURE 7-20. View / adjust calibration menu
Option 9 of the configuration menu gives the TERMINAL MODE menu (see
Figure 7-21). Choose whether CRC16-CCITT checksum verification is
required.
When terminal mode is set to 1 all terminal commands need a
CRC. For example “open 0;d2d5” a semi-colon is used to
indicate start of CRC in 4 byte ASCII hex. The CRC is
calculated either from the start of new line or after a [STX] up to
but not including the semicolon. ETX can follow the CRC if
required. The valid CRC can be read back for any command if
the CRC after the semi-colon is replaced with four `?’. For
example “open 0;????” the response will
be
[CRLF]CRC>D2D5<CRC[CRLF] so d2d5 is the
CRC.
NOTE
FIGURE 7-21. Terminal mode menu
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