Hello all, fairly new to M5, but have done embedded stuff for a while. I built this using UIFlow2, but also pasting the code below for those who prefer to see it in code.
Screenshot 2025-01-30 at 12.32.17 AM.png
I have 3 RFID readers hanging off a PAHub. I'm getting the RFID UIDs off the readers and storing them in a variable in the Loop. All good so far. I write them to variables RFIDZERO, RFIDONE and RFIDTWO (I was using other names, but thought it might have been getting confused with the other variable names).
Inside the do loops, RFIDZERO and RFIDONE get set to their correct values from the RFID tags. Immediately outside the do loop, I print them again and now, RFIDONE is equal to RFIDZERO's value. No other assignment operators or operation has taken place. WTF?
import M5
from M5 import *
from module import Module4In8Out
from hardware import I2C
from hardware import Pin
from unit import PAHUBUnit
from unit import RFIDUnit
module_4in8out_0 = None
i2c0 = None
file_0 = None
pahub_0 = None
rfid_0 = None
rfid_1 = None
rfid_2 = None
RFIDZERO = None
WritingRFIDs = None
RFIDONE = None
RFIDTWO = None
def btnA_wasClicked_event(state):
global module_4in8out_0, i2c0, file_0, pahub_0, rfid_0, rfid_1, rfid_2, RFIDZERO, WritingRFIDs, RFIDONE, RFIDTWO
WritingRFIDs = True
def setup():
global module_4in8out_0, i2c0, file_0, pahub_0, rfid_0, rfid_1, rfid_2, RFIDZERO, WritingRFIDs, RFIDONE, RFIDTWO
M5.begin()
Widgets.fillScreen(0x222222)
BtnA.setCallback(type=BtnA.CB_TYPE.WAS_CLICKED, cb=btnA_wasClicked_event)
module_4in8out_0 = Module4In8Out(address=0x45)
i2c0 = I2C(0, scl=Pin(33), sda=Pin(32), freq=100000)
pahub_0 = PAHUBUnit(i2c=i2c0, channel=0)
rfid_2 = RFIDUnit(PAHUBUnit(i2c=i2c0, channel=2))
rfid_1 = RFIDUnit(PAHUBUnit(i2c=i2c0, channel=1))
rfid_0 = RFIDUnit(PAHUBUnit(i2c=i2c0, channel=0))
WritingRFIDs = False
def loop():
global module_4in8out_0, i2c0, file_0, pahub_0, rfid_0, rfid_1, rfid_2, RFIDZERO, WritingRFIDs, RFIDONE, RFIDTWO
M5.update()
if not WritingRFIDs:
if rfid_0.is_new_card_present():
RFIDZERO = rfid_0.read_card_uid()
print((str('RFID_0: ') + str(RFIDZERO)))
rfid_0.close()
if rfid_1.is_new_card_present():
RFIDONE = rfid_1.read_card_uid()
print((str('RFID_1: ') + str(RFIDONE)))
rfid_1.close()
if rfid_2.is_new_card_present():
RFIDTWO = rfid_2.read_card_uid()
print((str('RFID_2: ') + str(RFIDTWO)))
rfid_2.close()
print((str('RFID_0: ') + str(RFIDZERO)))
print((str('RFID_1: ') + str(RFIDONE)))
print((str('RFID_2: ') + str(RFIDTWO)))
else:
file_0 = open('/flash/rfidtags.txt', 'w')
file_0.write(RFIDZERO)
file_0.write('\r\n')
file_0.write(RFIDONE)
file_0.close()
WritingRFIDs = False
print('Wrote the file')
if __name__ == '__main__':
try:
setup()
while True:
loop()
except (Exception, KeyboardInterrupt) as e:
try:
from utility import print_error_msg
print_error_msg(e)
except ImportError:
print("please update to latest firmware")
