Model 4200A-SCS Parameter Analyzer Reference Manual
Section 13: LPT library function reference
4200A-901-01 Rev. C / February 2017
13-155
Example
pulse_trig_polarity(VPU1, 0)
Sets the pulse card trigger output for negative polarity.
Also see
(on page 13-153)
(on page 13-155)
(on page 5-66)
pulse_trig_source
This command sets the trigger source.
Usage
int pulse_trig_source(int
instr_id
, long
source
);
instr_id
The instrument identification code of the pulse card, such as VPU1 or VPU2
source
Trigger source:
•
Software:
0
(default)
•
External – initial trigger only – rising:
1
•
External – initial trigger only – falling:
2
•
External – trigger per pulse – rising:
3
•
External – trigger per pulse – falling:
4
•
Internal trigger bus:
5
Pulse modes
Standard, Full Arb, Segment Arb
Details
This command sets the trigger source that is used to trigger the pulse card to start its output.
If the software trigger source selected, the
pulse_trig
command will select the trigger mode
(continuous, burst, or trig burst), and initiate the start of pulse output.
If an external trigger source selected, the
pulse_trig
command will select the trigger mode and
arm pulse output. Pulse output will start when the required external trigger pulse is applied to the
Trigger In connector of the pulse card. There is a trigger-in delay of 560 ns. This is the delay from the
trigger-in pulse to the time of the rising edge of the output pulse.
4220-PGU and 4225-PMU: Do not use the two external falling trigger sources
(
pulse_trig_source
function) with the positive trigger output polarity (
pulse_trig_polarity
function) on the master card that triggers itself and other subordinate cards. These two falling trigger
sources should only be used when an external piece of equipment is used to supply the trigger
pulses to the 4220-PGU and 4225-PMU. This applies to all three pulse modes (standard pulse,
Segment Arb, and full arb).
Because trigger source is a card-level setting and not a channel setting, using channel 1 or 2 will set
the card to the specified source card 1. Similarly, channel 3 or 4 will set the source for card 2.