Function protocol_main_loop

FluidNC/src/Protocol.cpp:240–315

int32_t  heapLowWaterReportTime = 0;

void protocol_main_loop() {
    add_watchdog_to_task();
    start_polling();

    // ---------------------------------------------------------------------------------
    // Primary loop! Upon a system abort, this exits back to main() to reset the system.
    // This is also where the system idles while waiting for something to do.
    // ---------------------------------------------------------------------------------
    for (;; vTaskDelay(1)) {
        if (activeChannel) {
            // The input polling task has collected a line of input
            if (gcode_echo->get()) {
                report_echo_line_received(activeLine, allChannels);
            }

            Channel* out_channel = Job::leader ? Job::leader : activeChannel;

            Error status_code = execute_line(activeLine, *out_channel, AuthenticationLevel::LEVEL_GUEST);

            // Tell the channel that the line has been processed.
            // If the line was aborted, the channel could be invalid
            if (!sys.abort()) {
                activeChannel->ack(status_code);
            }

            // Tell the input polling task that the line has been processed,
            // so it can give us another one when available
            activeChannel = nullptr;
        }

        // Auto-cycle start any queued moves.
        protocol_auto_cycle_start();
        protocol_execute_realtime();  // Runtime command check point.
        sys.process_changes();

        if (sys.abort()) {
            sys.set_abort(false);
        }

        // check to see if we should disable the stepper drivers
        // If idleEndTime is 0, no disable is pending.

        // "(ticks() - EndTime) > 0" is a twos-complement arithmetic trick
        // for avoiding problems when the number space wraps around from
        // negative to positive or vice-versa.  It always works if EndTime
        // is set to "timer() + N" where N is less than half the number
        // space.  Using "timer() > EndTime" fails across the positive to
        // negative transition using signed comparison, and across the
        // negative to positive transition using unsigned.

        if (idleEndTime && (getCpuTicks() - idleEndTime) > 0) {
            idleEndTime = 0;  //
            Axes::set_disable(true, false);
        }
        uint32_t newHeapSize = xPortGetFreeHeapSize();
        if (newHeapSize < heapLowWater) {
            heapLowWater = newHeapSize;
        }