Triggering and Gating 5
Keysight 53220A/53230A User’s Guide 191
The specific command which sets the gate start (open) source is:
[SENSe:]GATE:STARt:SOURce {IMMediate|EXTernal}
[SENSe:]GATE:STARt:SOURce? (query form)
– gate source IMMediate starts (opens) the measurement gate immediately 
after a system trigger is received and following any programmed system 
trigger and gate start delay. 
– gate source EXTernal sets the gate source to be specified by the command:
[SENSe:]GATE:EXTernal:SOURce  {BNC|INPut[1]|INPut2}
[SENSe:]GATE:EXTernal:SOURce? (query form)
– gate source BNC is the counter’s rear panel ‘Gate In/Out’ BNC. 
– gate source INPut[1] and INPut2 (represented by softkeys Chan 1 and 
Chan 2) are the counter’s channel 1 and channel 2 inputs. These sources are 
not available for time interval, pulse wid th, duty cycle, rise/fall time, or 
phase measurements.
External gate start signal polarity
When using the external gate sources listed, the polarity of the start gate signal is 
set (changed) with the command:
[SENSe:]GATE:STARt:SLOPe {POSitive|NEGative}
[SENSe:]:GATE:START:SLOPe? (query form)
OUTput:STATe OFF must be set when using gate source BNC. See “Enabling 
gate signals on the ‘gate in/out’ BNC” for more information and for information 
on using gate signals to synchronize other instruments.