What is the recommended way to test code containing TC2_MC2 functions?

[R4lfE]

I want to test code containing an MC_MoveRelative from the TC2_MC2 library. I was wondering what the recommended way to do this is.

Currently, I have a successfully running test that tests code containing MC_Reset with the following setup:

• A test Axis which is correctly configured and connected
• My implementation with calls to MC_Reset
• A test PLC project which runs in sequence
• A test suite containing my test
• The successful test itself is of the following form (omitted some unnecessary details):

VAR_INST
    objectUnderTest
    nCycleCounter
    nCycleLimit
    expected
END_VAR
----------
IF TEST_ORDERED('My test') THEN
    IF nCycleCounter = 0 THEN
        // Initialize my object under test
    END_IF

    objectUnderTest.Cycle(); // Perform a cycle containing MC_Reset

    actual := objectUnderTest.something;
    IF nCycleCounter = nCycleLimit OR actual = expected THEN
        Assert();
        TEST_FINISHED();
    END_IF
END_IF

When attempting a similar test of code containing MC_MoveRelative, the MC_MoveRelative function block goes into an error state after two cycles (Error 0x701). There are no axis errors or MC_Power errors. I'm unable to figure out what causes this error, especially since the test containing MC_Reset completes correctly.

I am not asking for debug help specifically (though if you have experience with this or have some suggestions, feel free to comment). My question is: Am I testing the code containing the MC_MoveRelative block correctly? What are your recommendations? I'm thinking of adding a testing flag in the implementation so all TC2_MC2 related code is bypassed during test execution but I would rather test the complete code.

[sagatowski]

My question is; does MC_MoveRelative need to be part of the SUT?
Is there any way you can abstract that away, and move it in as a dependency to your SUT instead?