Behavior of Function Blocks with the Inputs i_xEnable and i_xExecute and i_xErrorQuit

By setting the input i_xEnable to TRUE, the function block starts the enabling process. The function block continues initialization and the output q_xActive is set to TRUE. Once the initialization is finished and the function block is ready, the output q_xReady is set to TRUE.

A rising edge of the input i_xExecute starts the execution of the function block. The function block continues execution and the output q_xBusy is set to TRUE. A rising edge at the input i_xExecute is ignored while the function block is being executed.

Once the execution is finished, the outputs q_xDone or q_xError are set according to the result.

The output q_xDone indicates a successful execution and it remains TRUE until the next rising edge of the input i_xExecute.

If q_xError indicates TRUE, an error has been detected during execution. A renewed execution of the function block is not possible as long the error state is present. Certain error messages can be reset using the input i_xErrorQuit.

If the error state persists upon a rising edge of i_xErrorQuit, the function block must be disabled in order to reset the error state.

By setting the input i_xEnable to FALSE, the function starts the disabling process. Continue calling the function block as long as the output q_xActive is TRUE.