External trigger Sample Clauses

External trigger. AlazarTech digitizer boards can trigger on a signal connected to its TRIG IN BNC connector. Figure 2-4 External trigger connector on PCI/PCIe mounting bracket. To use an external trigger input: • Call AlazarSetTriggerOperation with TRIG_EXTERNAL as the trigger source identifier of at least one of the trigger engines; and • Call AlazarSetExternalTrigger to select the range and coupling of the external trigger input. The following code fragment configures a board to trigger when the signal connected to the TRIG IN falls below +2 V, assuming the signal’s range is less than ± 5V with DC coupling. // Calculate the trigger level code from the level and range double triggerLevel_volts = 2.; // trigger level double triggerRange_volts = 5.; // input range U32 triggerLevel_code = (U32)(128 + 127 * triggerLevel_volts / triggerRange_volts); // Configure trigger engine J to generate a trigger event // on the falling edge of an external trigger signal. AlazarSetTriggerOperation( handle, // HANDLE -- board handle TRIG_ENGINE_OP_J, // U32 -- trigger operation TRIG_ENGINE_J, // U32 -- trigger engine id TRIG_EXTERNAL, // U32 -- trigger source id TRIGGER_SLOPE_NEGATIVE, // U32 -- trigger slope id triggerLevel, // U32 -- trigger level (0 – 255) TRIG_ENGINE_K, // U32 -- trigger engine id TRIG_DISABLE, // U32 -- trigger source id for engine K TRIGGER_SLOPE_POSITIVE, // U32 -- trigger slope id 128 // U32 -- trigger level (0 – 255) ); // Configure the external trigger input to +/-5V range, // with DC coupling AlazarSetExternalTrigger( handle, // HANDLE -- board handle DC_COUPLING, // U32 -- coupling id ETR_5V // U32 -- external range id );