RPI.GPIO Help

alister alister.nospam.ware at ntlworld.com
Thu Aug 20 11:54:21 EDT 2015


On Thu, 20 Aug 2015 16:45:53 +0100, MRAB wrote:

> On 2015-08-20 16:12, John McKenzie wrote:
>>
>>   Thanks for the reply. Also, thanks to Laura who replied via email.
>>
>>   Tried a bunch of things based off these comments and I always ended
>>   up
>> with one of two situations, the channel conflict error, or an instant
>> run and quit issue. This new version of the code runs but is
>> unresponsive. I removed loops then put in a short sleep loop. while
>> True:
>>      time.sleep(0.1) It could be my hardware is done up wrong, but it
>> looks OK. Perhaps it is always sleeping.
>>
>>   Anyone at all know about GPIO and the Pi under the Python library
>> RPi.GPIO please feel free to advise as to what the problem is most
>> likely to be.
>>
>>
>> import atexit import time from blinkstick import blinkstick import
>> RPi.GPIO as GPIO
>>
>> led = blinkstick.find_first()
>> colour = 0 timered = 0 timeyellow = 0 timeblue = 0 timestamp =
>> time.strftime("%H:%M:%S")
>>
>>
>>
>> GPIO.setmode(GPIO.BCM)
>> GPIO.setup(22, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
>> GPIO.setup(23, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
>> GPIO.setup(24, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
>>
>>
>>
>> def red_button(channel):
>>      colour = 1 while colour == 1:
>>          print "Red Button pressed" timered += 1
>>
>>
>> def yellow_button(channel):
>>      colour = 2 while colour == 2:
>>          print "Yellow Button pressed"
>>          timeyellow += 1
>>
>>
>> def blue_button(channel):
>>      colour = 3 while colour == 3:
>>          print "Blue Button pressed" timeblue += 1
>>
>> GPIO.add_event_detect(23, GPIO.RISING, callback=yellow_button,
>> bouncetime=200)
>> GPIO.add_event_detect(22, GPIO.RISING, callback=red_button,
>> bouncetime=200)
>> GPIO.add_event_detect(24, GPIO.RISING, callback=blue_button,
>> bouncetime=200)
>>
>> while True:
>>      time.sleep(0.1)
>>
>> def exit_handler():
>>      print '\033[0;41;37mRed Team:\033[0m ', timered print
>>      '\033[0;103;30mYellow Team:\033[0m ', timeyellow print
>>      '\033[0;44;37mBlue Team:\033[0m ', timeblue flog =
>>      open('flag1log.text', 'a')
>>      flog.write(timestamp + '\n' + 'Red Team: ' + str(timered) + '\n' +
>> 'Yellow Team: ' + str(timeyellow) + '\n' + 'Blue Team: ' +
>> str(timeblue) + '\n')
>>      flog.close()
>> atexit.register(exit_handler)
>> GPIO.cleanup()
>>
>>
> The function 'red_button' will be called when a rising edge is detected.
> 
> In that function, you're assigning to 'colour' but not changing it in
> the loop, so it's basically just a busy loop. However, you're trying to
> change 'timered', which is a global variable, but you're not declaring
> it as global, so that will raise UnboundLocalError.
> 
> Similar remarks apply to the other two callbacks.
> 
> I think you'd be better off detecting both the rising and falling edges,
> with a callback for each, recording when each edge occurred (duration of
> press = time of falling edge - time of rising edge).

you may also find it more useful to post this to Comp.sys.raspberry_pi
the python skills may not be quite as in depth as here but they will know 
more about the raspberry hardware



-- 
The easiest way to get the root password is to become system admin.
	-- Unknown source



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