Vaisala HMP155 - Manual (Page 26)

USER'S GUIDE____________________________________________________________________
24 _______________________________________________________________ M210912EN-C
Serial Line Communication
Connect the probe to a PC, for example, by using a USB cable (optional
accessory item: 221040). Connect the USB cable to the 8-pin connector
on the bottom of the probe. Before you can use the USB cable, you must
install the provided USB driver on your PC, see Installing the Driver for
the USB Cable on page 25.
NOTE When using the USB-cable, no separate power unit is needed. The probe
is powered through the USB port.
NOTE Heating and Purge functions may not work properly with the USB cable
due to limited USB powering capability. This depends on the computer
used and environmental conditions.
HMP155 does not echo typed characters back to the terminal screen. To
see the commands you type, you need to enable the "local echo" -setting
in your terminal program.
A new command cannot be received while the instrument is sending data
out. Wait until the instrument has completed its response before entering
the next command.
NOTE In the RUN mode, the instrument may send the measurement data
message while you are typing the S command to stop the sending.
Therefore, you may need to repeat the S command. This must be noted
especially when designing computer programs to access the HMP155.
You can also use the Esc key on your keyboard to stop the sending.
Table 5 Default Serial Communication Settings
Parameter Value
Bauds 4800
Parity Even
Data bits
7
Stop bits 1
Flow control None