Real time error signal displaying

[Andrea Fantini]

Hello everybody,

I am currently implementing PID function on my blacs driver for a MOG Labs QRF.

I managed to set up its PID settings through blacs tabs and I am trying now to display in real time the PID error function that can me asked through command line. 

In my main_worker I am already able to write the result down on my terminal window but I am wondering if there is a strategy that lets me display the value in a more GUI version.

I tried to set up a slider whose position is changed continously trhough the reading of the error signal but two problems arose:

1.  my real time idea was to exploit while-ish loop that are not much liked by blacs.
2.  result to yield(....self.dev.ask()) is not giving me nothing but 'None'.

Should I set a general property such as self.....errorSignal that I can call to set the slider position or is there any better option?

I leave you pieces of code to understand better what i am trying to do.:

    def display_errorSignal(self):
        if not self.error_display:
            self.ui.pushButton_errorSignal.setIcon(self.stop_icon)
            self.error_display = True
            while True:
                signal=self.parent.event_queue.put(allowed_states=MODE_MANUAL, queue_state_indefinitely=True, delete_stale_states=False,
                                data=[self._display_errorSignal, [[self.channel], {}]])
                if signal is not None:
                    self.ui.slider_ErrorSignal.setSliderPosition(signal)
                    time.sleep(0.5)
                else:
                    self.ui.slider_ErrorSignal.setSliderPosition(0)
                    break
        else:
            self.ui.pushButton_errorSignal.setIcon(self.start_icon)
            self.error_display = False
            self.ui.slider_ErrorSignal.setSliderPosition(0)

    def _display_errorSignal(self, parent, channel):
        result = yield( self.parent.queue_work(self.parent.primary_worker,'errorPID', channel) )
        self.ErrorSignal=result
        return result

---------------------------------------------------------------------------------

    def errorPID(self, channel):
        # Andre: returns the value of the error signal fed into the PID control loop, for diagnostic purposes
        result = self.dev.ask('PID, ERROR, %i' % (channel + 1))
        value = float(result[0:4])
        print(f'displaying error signal: {value}')
        return value

Thank you all for the attention and in case for the help.

Best,

Andre