You're reading the documentation for an older, but still supported version (GL013300).
For information on the latest version, please have a look at GL013301.

del_modbus_signal (Auto Mode)

This section explains how to use del_modbus_signal to remove a previously registered Modbus signal from the controller.

This function is used mainly during configuration or maintenance to clean up unused or incorrect Modbus mappings.

Typical usage

  • Remove outdated Modbus addresses when devices are replaced.

  • Clean up development/testing signals before deployment.

  • Prevent symbol conflicts by deleting unused entries.

  • Maintain clean and consistent Modbus configuration.

Note

  • strSymbol must match an existing registered Modbus signal.

  • Do not delete a signal that is being used by an active Auto Mode sequence.

  • Best used during setup or before production runs.

Example: Removing an Unused Modbus Signal

#include "DRFLEx.h"
#include <cstdio>
using namespace DRAFramework;

int main() {
    CDRFLEx drfl;

    // Delete an unused Modbus signal
    if (!drfl.del_modbus_signal("CONVEYOR_START")) {
        printf("Failed to delete Modbus signal.\n");
        return -1;
    }

    printf("Modbus signal removed successfully.\n");
    return 0;
}

In this example, an old Modbus mapping is removed to prevent symbol duplication or configuration errors.

Tips

  • Only delete signals that are confirmed to be unused.

  • Keep Modbus mapping tables organized when managing multiple devices.

  • Use get_modbus_input and set_modbus_output to verify active mappings.

  • Follow consistent naming conventions when adding or deleting signals.