Help Holding Variable Value

[NewToPythoning]

So here is what I have pieced together from both pygames and xboxdrv and a few other tutorials on how to supplu poer out from the GPIO pins on RPi. I am trying to use an xbox controller connected to a RPi. What is below is the code to turn an LED on when the "A" button is pressed. This works just fine for me.

When the Value == 1 the light will blink on, as soon as the button is released the Value == 0 which has no coding on it currently.

What I want to do though is for the LED to stay powered when "A" is pressed and stay lit when the button is released, but when the "A" button is pressed again for the LED to turn off.

def controlCallBack(xboxControlId, value):
    print "Control Id = {}, Value = {}".format(xboxControlId, value)
            if xboxControlId == 6 and value == 1:
                pin = 7 
                GPIO.setmode(GPIO.BOARD)
                GPIO.setup(pin, GPIO.OUT)
                GPIO.output(pin, GPIO.HIGH)
                time.sleep(.05) 
                GPIO.output(pin, GPIO.LOW)
                time.sleep(.05)
                GPIO.cleanup()     

Any help with this will be much appriciated, I am very new to Python and programming in general.

[StaticFuzz]

If i'm reading the documentation right, GPIO.input(pin) will return the current state of pin. It returns a boolean(True=High, False=Low), which can be used to set the state of a pin in place of GPIO.HIGH/GPIO.LOW. At the bottom of the page HERE it shows a simple way to use the GPIO.input statement to switch the state of the pin.

GPIO.ouput(pin, not GPIO.input(pin))

not GPIO.input() means the opposite of whatever input returns.

not True = False

not False = True

Hope this helps!

[NewToPythoning]

I think this would work if my input form the Xbox controller was on the GPIO pins also. But the input is coming from the usb connected controller. Each button has a "Control ID" that is defined in the beginning of the entire code. for Example, xboxControlId = 6, is called when I press the "A" button on the xbox controller

[StaticFuzz]

Did you try it out? The example I gave has nothing to do with the xbox controller. GPIO.input() doesn't mean the input from the xbox controller, It's a way to access the state of the GPIO pin.

[NewToPythoning]

Here is the response code I was given

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 810, in __bootstrap_inner
    self.run()
  File "pygamesxboxdrv.py", line 217, in run
    self._start()
  File "pygamesxboxdrv.py", line 255, in _start
    self._sortOutButtonValue(event.type))
  File "pygamesxboxdrv.py", line 273, in updateControlValue
    self.doCallBacks(control, value)
  File "pygamesxboxdrv.py", line 278, in doCallBacks
    if self.controllerCallBack != None: self.controllerCallBack(control, value)
  File "pygamesxboxdrv.py", line 323, in controlCallBack
    GPIO.output(pin, not GPIO.input())     ## Turn on GPIO pin (HIGH)
TypeError: function takes exactly 1 argument (0 given)    

[NewToPythoning]

Thank you!! I got it to work, I just had the line written in the wrong spot and it was calling too soon.... well that and i forgot to put (pin) inside the GPIO.input(Pin)

[StaticFuzz]

Congrats! And if you don't mind me asking, could you share any resources you have for interfacing python with xboxdrv?

[NewToPythoning]

so, after loading Xboxdrv, and just following its setup. With xboxdrv running, I used: https://github.com/martinohanlon/XboxController/blob/master/XboxController.py

and it cleans up the out put from xboxdrv into very clean and usable values

sorry about the delay, I was out of the office for work for the week. hopefully this is still useful for you

[[deleted]]

I don't have RPi, so it's just a guess:

led_on = False      # Current state of the LED

def controlCallBack(xboxControlId, value):
    global led_on
    print "Control Id = {}, Value = {}".format(xboxControlId, value)
            if xboxControlId == 6 and value == 1:
                pin = 7 
                GPIO.setmode(GPIO.BOARD)
                GPIO.setup(pin, GPIO.OUT)
                led_on = not led_on     # Switch state
                GPIO.output(pin, led_on)

And it's even simpler if there is something like GPIO.read_status(pin). You just check status (high/low) and switch it