ML2439A USB Power Meter User Guide : SCPI Commands : INITiate and ABORt Commands
 
INITiate and ABORt Commands
The purpose of the INITiate group of commands is to start and control the process of data acquisition once a measurement has been configured. Depending on settings, the ML2439A USB Power Meter may be commanded to begin either a single measurement (INITiate:CONTinuous OFF) which stops when complete, or enter a “free-run” mode where data acquisition occurs continuously (INITiate:CONTinuous ON). The ABORt command terminates any operation in progress and prepares the instrument for an INITiate command. In some operating modes, the INITiate commands do not actually start measurements, but rather arms a hardware trigger, which is then used to gate the actual measurements cycle.
ABORt
Description:
Terminates any measurement in progress and resets the state of the trigger system. Note that ABORt will leave the measurement in a stopped condition with all current measurements cleared, and forces INITiate:CONTinuous to OFF.
Syntax:
ABORt
Argument:
None Valid Modes: Any
 
INITiate:CONTinuous
Description:
Set or return the data acquisition mode for single or free-run measurements. If INITiate:CONTinuous is set to ON, the ML2439A immediately begins taking measurements (Modulated, CW and Statistical Modes), or arms its trigger and takes a measurement each time a trigger occurs (Pulse Mode). If set to OFF, the measurement will begin (or be armed) as soon as the INITiate command is issued, and will stop once the measurement criteria (averaging, filtering or sample count) has been satisfied. Note that INITiate:IMMediate and READ commands are invalid when INITiate:CONTinuous is set to ON; however, by convention this situation does not result in a SCPI error.
Syntax:
INITiate:CONTinuous <Boolean> Argument: <Boolean> = { 0, 1, OFF, ON } Valid Modes: Any
 
INITiate[:IMMediate[:ALL]]
Description:
Starts a single measurement cycle when INITiate:CONTinuous is set to OFF. In Modulated Mode, the measurement will complete once the power has been integrated for the full FILTer time. In Pulse Mode, enough trace sweeps must be triggered to satisfy the AVERaging setting. In Statistical Mode, acquisition stops once the terminal condition(s) are met. In each case, no reading will be returned until the measurement is complete. This command is not valid when INITiate:CONTinuous is ON, however, by convention this situation does not result in a SCPI error.
Syntax:
INITiate[:IMMediate[:ALL]]
Argument:
None Valid Modes: Any
Restrictions:
INITiate:CONTinuous must be OFF