Created on 2010-11-25 04:01:00

Question:
We use an APx audio analyzer for a production test application in which test operators repeatedly run the sequence in a project file. Is there a way to make the sequence run in a loop automatically without the need for the operator to press the run sequence button each time? We would like the sequence to automatically repeat from the beginning after the APx500 project report is generated.

Answer:
You can easily set up the APx500 software to run in a loop by setting the Sequence Properties appropriately and connecting a simple switch to the Aux Control In port on the back of the instrument.

Select Project > Sequence Properties from the menus, or right-click on the project name at the top of the measurement navigator tree to open the Sequence Properties window. On the Start tab, check Aux Control In Starts Sequence, and then check the boxes for each of the Aux Control In lines (1 – 8). Then, set lines 2 – 7 to logic high (a value of 1), and leave line 1 set to low (a value of zero).

Now, connect a switch between pins 1 and 9 on the Aux Control In port. The lines are normally held high by internal pull-up resistors, so closing the switch will ground line 1 and pull it low, satisfying the conditions set above to automatically start the sequence. If you use a regular latching type of switch, the sequence will start when you close the switch and will keep repeating until you open it. Alternately, if you use a normally-open footswitch, an operator can press it to manually re-start the sequence each time a new DUT is ready to be tested.

Applies to: APx.