RPi GPIO Flashing LED

[nickayres]

The code works a treat in that button pressed LED ON button pressed again LED OFF. What I am trying to do is get the LED to flash when it is ON rather than permanently lit. I think I need to put in a while True loop but unsure where. Placing it in the def Loop() does make it flash but it flashes during the on and off state. Whats confusing me is the def swLed section as this is the place where the LED is turned on and off but if I put the loop in there nothing happens. Any help most appreciated - still trying to get my head around Python! Thanks

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import RPi.GPIO as GPIO import time   LedPin = 11                                                     # pin11 --- led BtnPin = 12                                                     # pin12 --- button   Led_status = 1   def setup():         GPIO.setmode(GPIO.BOARD)                                # Numbers GPIOs by physical location         GPIO.setup(LedPin, GPIO.OUT)                            # Set LedPin's mode is output         GPIO.setup(BtnPin, GPIO.IN, pull_up_down=GPIO.PUD_UP)   # Set BtnPin's mode is input, and pull up to high level(3.3V)         GPIO.output(LedPin, GPIO.HIGH)                          # Set LedPin high(+3.3V) to off led   def swLed(ev=None):         global Led_status         Led_status = not Led_status         GPIO.output(LedPin, Led_status)                         # switch led status(on-->off; off-->on)   def loop():         GPIO.add_event_detect(BtnPin, GPIO.FALLING, callback=swLed, bouncetime=200) # wait for falling, set bouncetime to prevent callback function                                                                                     # from being called multiple times when the button is pressed         while True:                 time.sleep(1)                                   # Don't do anything   if __name__ == '__main__':                                      # Program start from here         setup()         try:                 loop()         except KeyboardInterrupt:                               # When 'Ctrl+C' is pressed, the child program destroy() will be  executed.                 destroy()

[gontajones]

I think you'll have to start a Thread in swLed() that could trigger a while loop to blink the LED (if button is pressed [ON]).
If the press button is OFF you'll have to set a "global stop variable" (keep_blinking = False) to break the blink LED loop.

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def my_thread_function():     led_state = 1     while keep_blinking:         GPIO.output(LedPin, led_state)         led_state = not led_state         time.sleep(0.1)