I am developping a auto-test program according to GPIB to connect to E4404B, spectrum analyzer, than I found some example code here,
/*Reset the instrument*/
viPrintf(viESA,"*RST\n");
/*Set Y-Axis units to dBm*/
viPrintf(viESA, "UNIT
OW DBM\n");
/*Set the analyzer center frequency to 50MHZ*/
viPrintf(viESA,"SENS:FREQ:CENT 50e6\n");
the strange thing is that "UNITOW DBM" can not be found anywhere, in standard SCPI command or instrument specified command, does anyone can explain where this command comes from?