Hello using python-function i'm not able to get get the variable value import sys sys.path.append("/home/pi/.local/lib/python3.9/site-packages") from pigpio_encoder.rotary import Rotary import threading import time global my_counter my_counter = 0 def sw_short(): pass def up_callback(counter): global my_counter if counter%40==0: my_counter+=1 msg['payload'] = {'pos_x':my_counter} print(msg) #print(my_counter) def down_callback(counter): global my_counter if counter%40==0: my_counter-=1 msg['payload'] = {'pos_x':my_counter} return msg #return my_counter #print(my_counter) def pippo(): global my_counter print(my_counter) time.sleep(0.3) pippo() my_rotary = Rotary(clk_gpio=13, dt_gpio=12,sw_gpio = 17) my_rotary.setup_rotary( min=-1000000, max=1000000, debounce = 1, up_callback=up_callback, down_callback=down_callback,) #rotary_callback=rotary_callback, my_rotary.setup_switch(sw_short_callback=sw_short) return msg This is the code, i'm not able to desplay the value of my_counter [ { "id": "f23f10101329d95f", "type": "python-function", "z": "a2713db36e62f1e7", "name": "Encoder", "func": "import sys\nsys.path.append(\"/home/pi/.local/lib/python3.9/site-packages\")\nfrom pigpio_encoder.rotary import Rotary\nimport threading\nimport time\nglobal my_counter\nmy_counter = 0\n\ndef sw_short():\n pass\n\ndef up_callback(counter):\n global my_counter\n if counter%40==0:\n my_counter+=1\n msg['payload'] = {'pos_x':my_counter}\n print(msg)\n #print(my_counter)\n\ndef down_callback(counter):\n global my_counter\n if counter%40==0:\n my_counter-=1\n msg['payload'] = {'pos_x':my_counter}\n return msg\n #return my_counter\n #print(my_counter)\n \ndef pippo():\n global my_counter\n print(my_counter)\n time.sleep(0.3)\n pippo()\n\n\nmy_rotary = Rotary(clk_gpio=13, dt_gpio=12,sw_gpio = 17)\nmy_rotary.setup_rotary( min=-1000000,\n max=1000000,\n debounce = 1,\n up_callback=up_callback,\n down_callback=down_callback,)\n #rotary_callback=rotary_callback,\nmy_rotary.setup_switch(sw_short_callback=sw_short)\nreturn msg\n# x = threading.Thread(target=pippo)\n# x.start()\n\n", "outputs": 1, "x": 220, "y": 100, "wires": [ [ "393990a61c77173e" ] ] } ]

when you run python are you using the -u parameter to ensure it flushes any results to the output ?

no i never put the -u, where i have to put it ? [image] this is what i see when i run the flow but i have no output

Ah sorry didn’t spot you were using a custom node. I usually just call python -u from an exec node

I remember that others have had problems using that node, as Dave suggests, you might be better using an exec node to call your script. If you do that make sure you put the full path to the script in the exec node.

Hello Now i'm in this situation but no output: [image] inject [image] exec [image] Debug [image] Python code import RPi.GPIO as GPIO from time import sleep counter = 10 Enc_A = 13 Enc_B = 12 def init(): print("Rotary Encoder Test Program") GPIO.setwarnings(True) GPIO.setmode(GPIO.BCM) GPIO.setup(Enc_A, GPIO.IN) GPIO.setup(Enc_B, GPIO.IN) GPIO.add_event_detect(Enc_A, GPIO.RISING, callback=rotation_decode, bouncetime=10) return def rotation_decode(Enc_A): global counter sleep(0.002) Switch_A = GPIO.input(Enc_A) Switch_B = GPIO.input(Enc_B) if (Switch_A == 1) and (Switch_B == 0): counter += 1 print("direction -> ", counter) while Switch_B == 0: Switch_B = GPIO.input(Enc_B) while Switch_B == 1: Switch_B = GPIO.input(Enc_B) return elif (Switch_A == 1) and (Switch_B == 1): counter -= 1 print("direction <- ", counter) while Switch_A == 1: Switch_A = GPIO.input(Enc_A) return else: return def main(): try: init() while(True) : sleep(1) except KeyboardInterrupt: GPIO.cleanup() if __name__ == '__main__': main() I really don't know why i never see any value in the debug.

Check all outputs of the exec node, set the debug nodes to show the full message. Add some debug output to your script to see what is happening and what is not happening.

hello i start from easy test just for understand the problem if i do so: [image] [image] as you can see in the debug i have the return value but how can do if the return value is inside a def for example: def test() msg = 'test' return test while True: test() it run but i don't have any return value

i have solved this issue doing this: global pippo def test(): global pippo pippo = 'test' return pippo while True: test() msg['payload'] = {'pippo':pippo} return msg but i don't understand why in node-red i have the msg one time and not repeated. But my big problem is this: from pigpio_encoder.rotary import Rotary global my_counter my_counter = 0 def sw_short(): pass def up_callback(counter): global my_counter if counter%40==0: my_counter+=1 print(my_counter) return my_counter def down_callback(counter): global my_counter if counter%40==0: my_counter-=1 print(my_counter) return my_counter my_rotary = Rotary(clk_gpio=13, dt_gpio=12,sw_gpio = 17) my_rotary.setup_rotary( min=-10000, max=10000, debounce = 1, up_callback=up_callback, down_callback=down_callback,) #rotary_callback=rotary_callback, my_rotary.setup_switch(sw_short_callback=sw_short) msg['payload'] = {'my_counter':my_counter} return msg Always return [image] it return my_counter = 0 because he get the value from the beginning but not when the value change can you tell me where is my mistake Thanks

I am not at home in python, but aren't variables global by default if they are defined outside a function ? ie. can you remove all the "global" definitions ?

sorry guys but i really don't understand: from pigpio_encoder.rotary import Rotary global my_counter my_counter = 0 def sw_short(): pass def up_callback(counter): global my_counter if counter%40==0: my_counter+=1 print(my_counter) msg['payload'] = {'my_counter':my_counter} return msg def down_callback(counter): global my_counter if counter%40==0: my_counter-=1 print(my_counter) msg['payload'] = {'my_counter':my_counter} return msg my_rotary = Rotary(clk_gpio=13, dt_gpio=12,sw_gpio = 17) my_rotary.setup_rotary( min=-10000, max=10000, debounce = 1, up_callback=up_callback, down_callback=down_callback,) #rotary_callback=rotary_callback, my_rotary.setup_switch(sw_short_callback=sw_short) msg['payload'] = {'my_counter':my_counter} return msg i get only the first msg object with my_counter = 0 then when i move the encoder in the node-red shell i get all the print message : [image] but i get no return object. dear bakman2 in node-red if i never set as global the my_counter variable i get: NameError: name 'my_counter' is not defined Any help will be appreciated

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Python function return variable

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cymplecy 26 January 2023 16:06 20

Just linking in case you find this easier

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Python function return variable

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