Calling User Functions from BT-Basic

 

Calling User Functions from BT-Basic

If you prefer to control remote instruments from the BT-Basic testplan, see Example 7. Although this method produces the same results as Example 6, the frequent interaction between BT-Basic and ATL make this a more complex way to do the test.

Example 7 has an analog test that uses a high-frequency coaxial port ("FREQ_CNTR_HIGH" and "FREQ_CNTR_LOW") on the module to connect a frequency counter, FREQ_CNTR, to two nodes ("Node1" and "Node2") on the DUT and then make a measurement. The example works as follows:

1   BT-Basic starts the instrument server, calls a user function that sets the frequency counter to a known condition, and executes the analog functional test, "measure1".

2   ATL instructs the ASRU Card to make the connections between the frequency counter and the DUT and then passes control back to BT-Basic.

3   BT-Basic calls a function that makes the measurement, and stores the result in variable "F" so that it can be passed to ATL.

4   An ATL "report analog" statement evaluates the results.

Example 7    Controlling instruments from BT-Basic using rcall

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! IN THE BT-Basic TESTPLAN:

!    >>> Near the beginning of the testplan <<<

         . . .

   if nrun = 1 then

         . . .

      call Initialize_IServer            ! Start instrument server once

         . . .                           ! when the testplan is run.

   end if

         . . .

!    >>> In the main body of the testplan <<<

         . . .

   rcall FREQ_CNTR_SETUP                 ! Initialize the counter.

   test "measure1"; F                    ! Begin analog functional test.

   rcall FREQ_CNTR_SETUP_READ(F)         ! Make measurement, put result in "F".

   test cont                             ! Go to analog functional test.

         . . .

!    >>> With subroutines near the end of the testplan <<<

         . . .

   sub Initialize_IServer

      rinit "C_Server";program btgetenv$("AgilentICT_ROOT")&"/boards/my_board/workfile.uci", servicetype "UCI"

                                         ! Starts instrument server.

   subend

         . . .

 

! IN AN ANALOG FUNCTIONAL TEST CALLED "measure1":

!

   test powered analog; F

      connect "FREQ_CNTR_HIGH" high to "Node1"     ! Make connections between

                                                   ! frequency counter and DUT.

      pause                                        ! Return to BT-Basic.

      report analog 10, 5, F                       ! Evaluate the results.

   end tests

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In more complex tests the interaction between BT-Basic and ATL, via pause and test cont statements, becomes even more frequent. This additional complexity is why we recommend that you call the user functions from ATL, as described earlier.