Vaisala PTU300 - Page 152

USER'S GUIDE____________________________________________________________________
150 _________________________________________________________________ M210796EN-F
5. Open a terminal program, and connect to the service port. The
fixed settings serial line settings of the service port are
19200, 8, 1, N.
6. Use the SMODE command to enable the MODBUS mode:
>smode modbus
Serial mode : MODBUS
>
7. If necessary, use the SERI command to check and/or change the
serial interface settings for the User Port. For example, to set the
User Port serial settings to 19200 N 8 1, issue the following
command:
>seri 19200 N 8 1
NOTE
The number of data bits must always be 8 for MODBUS RTU.
Serial MODBUS interface of the PTU300 does not work with baud rates
115, 150, and 300 b/s.
8. Use the ADDR command to set the MODBUS address of the
transmitter. For example, to set the MODBUS address to 52, issue
the following command:
>addr 52
You must set a non-zero address or MODBUS RTU will not work.
9. The MODBUS configuration is now complete. Reset or power
cycle the transmitter to enable the MODBUS mode, and proceed
with the installation of the transmitter and the wiring of the serial
interface.