Service manual

52
Level Triggers (*TRG and TRIG command)
The following program continuously toggles all labeled signal lines in Figure 3-8 in the indicated direction.
10 LOOP
20 OUTPUT 705;"CURR:LEV;TRIG 5"
30 OUTPUT 705;"TRIG:SOUR BUS"
40 OUTPUT 705;"*TRG"
50 OUTPUT 705;"CURR 1"
60 END LOOP
70 END
The next program does essentially the same thing as the previous one except it lets you manually step through the program
to toggle the signal lines. Press [Continue] after each pause to continue the program.
10 OUTPUT 705;"CURR:LEV;TRIG 5"
20 OUTPUT 705;"TRIG:SOUR BUS" !TOGGLE ON RUN
30 PAUSE
40 OUTPUT 705;"*TRG" !TOGGLE ON TRG
50 PAUSE
60 OUTPUT 705;"CURR 1" !TOGGLE ON LEV
70 END
Note that READ_TRIG (U210-11) is high at power on. When stepping through the program, READ_TRIG goes low at line
30 and high again at line 10, RESET_TRIG (U208-2) is also high at power on and goes low in 10
µs pulse intervals. This
signal is easier to see using the first program.
Group Enable Trigger (GET function)
Note that P_TRIG (U208-12) is used via firmware to generate Bus triggers. GET_EN (U208-5) is always true and is NOT
used to generate triggers.
When running the following program, observe that P_TRIG (U208-12) pulses high, and PRI_TRIG (U215-11) toggles low.
10 OUTPUT 705;"TRIG:SOUR BUS"
20 LOOP
30 OUTPUT 705;"*TRG"
40 WAIT .1
50 END LOOP
60 END
External Triggers
To generate external triggers for this circuit, send the string "TRIG:SOUR EXT" and observe that U207-10, U247-3, and
U215-11 pulse whenever TRIG_IN is shorted to common (short TB201-1 to TB201-4).