User's Guide _______________________________________________________________________ 
42  ___________________________________________________________________ M211659EN-C 
Show Command List 
Use the HELP command to list the currently available serial commands. 
If the PASS command has not been used, only the basic serial commands 
are available. 
HELP<cr> 
Example (basic serial commands from a transmitter model with analog 
outputs, advanced commands are not enabled): 
>help 
? 
CALCS 
ECHO 
ENV 
ERRT 
ERRS 
FORM 
HELP 
INTV 
PASS 
R 
RESET 
SDELAY 
SEND 
SNUM 
STATUS 
UNIT 
VERS 
 
Measurement Settings 
Set Environmental Parameters 
Use the ENV command to set environmental parameters that affect the 
measurement. For GMW90 series transmitters you can set the ambient 
pressure value that is used for pressure compensation of CO
2
 
measurement and calculated humidity parameters. 
ENV [pressure]<cr> 
 
Example: 
>env 1013.3 
Pressure (hPa)      : 1013.3