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 Keg scale with LEDs to indicate percent of full, push notification when beer served
#1
Most recent edit is the Reset button to re-establish what full is. The goal is to use the same code for a variety of beers that would all have different full weights. Also, this could be used for placing a 12 pack on the scale and using the reset to "recalibrate" the scale.

Behold the code:
# Scale project that uses a scale to determine the volume of beer in the keg.
# A row of LEDs indicates the state of the program and the volume of the keg.
# A requests post initiates a push notification to my phone when the weight of the keg changes.
  
import time
import sys
import requests
from gpiozero import LED
  
  
#Define LED indicators - these are GPIO numbers
LED1 = LED(21) #Blue
LED2 = LED(26) #Red
LED3 = LED(20) #Amber
LED4 = LED(19) #Green
LED5 = LED(16) #Green
LED6 = LED(13) #Green
LED7 = LED(6) #Green
LED8 = LED(12) #Green
LED9 = LED(5) #Pink
Reset = Button(4) #Button to reset the variable "full" to the current scale value
 
 
EMULATE_HX711=False
  
referenceUnit = 1
  
if not EMULATE_HX711:
    import RPi.GPIO as GPIO
    from hx711 import HX711
else:
    from emulated_hx711 import HX711
  
def moving_average(prev_average, new_value, num_steps = 5.0):
   return (prev_average * (num_steps - 1) + new_value) / num_steps
 
def reset_full():
    full = keg1
     
average = weight = 400000  #just a value close to what a newly deployed keg would be
w_threshold = 2000  #approximate value of 3-4 fluid ounces of the beer 
  
def cleanandexit():
    print("Cleaning...")
    if not EMULATE_HX711:
        GPIO.cleanup()        
    print("Bye!")
    sys.exit()
  
hx = HX711(27, 22)
hx.set_reading_format("MSB", "MSB")
hx.set_reference_unit(1)
hx.reset()
hx.tare()
  
print("The scale is ready")  
print("put the keg on...")
  
LED9.blink(.2,3)  # indication that the scale is running - not blinking means program crash
start = time.time()
  
while True:
    try:        
        keg1 = hx.get_weight(5)
        weight = keg1
        keg1 = round(keg1,3)
        start_weight = keg1
         
        print(keg1, average)
        if time.time() - start > 5:
            weight = keg1
            lost_weight = average - keg1
            lost_weight = round(lost_weight,3)
            if lost_weight > w_threshold:
               #r = requests.post("https://bit.ly/editedforprivacy")  #Join URL that triggers push notification to my phone when beer is served
               print("You got served")
               average = keg1  #resets average to new keg1 value for faster recovery
            print(lost_weight)  #visual indication of how much was poured - one pint is about 8400
            average = moving_average(average, weight)
            average = round(average,3)
            start = time.time()
            Reset.when_pressed = reset_full
 #These lines get the percent of full value to properly run the LEDs
            full = keg1 #a full keg is typically around 505000 to 516000
            empty = 89000  #an empty keg shows approx 89000 when placed on the scale
            scale = 100 / (full - empty)
            percent_full = (weight - empty) * scale
 
  
        if 1 >= percent_full <= 102: #keg is outside of usable range - flashes when keg is missing (indicating tare is complete at startup)
            LED1.blink(.2,.2)
        else:
            LED1.off()
  
        if 1.1 >= percent_full >= 5: #Red less than 5% - DANGER
            LED2.blink(.5,.5)
        else:
            LED2.off()
              
        if 100 >= percent_full >= 10: #Amber less than 10% - Warning
            LED3.on()
        else:
            LED3.off()
              
        if 100 >= percent_full >= 20: #  Green 10-20% - Caution
            LED4.on()
        else:
            LED4.off()
              
        if 100 >= percent_full >= 40: #Green2 20-40%
            LED5.on()
        else:
            LED5.off()
              
        if 100 >= percent_full >= 60: #Green3 40-60%
            LED6.on()
        else:
            LED6.off()
              
        if 100 >= percent_full >= 80: #Green4 60-80%
            LED7.on()
        else:
            LED7.off()
              
        if 100 >= keg1 >= 80.1: #Green5 80-100%
            LED8.on()
        else:
            LED8.off()
  
  
        hx.power_down()
        hx.power_up()
        time.sleep(1)
  
  
    except (KeyboardInterrupt, SystemExit):
  
        cleanandexit()
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#2
Typo on line 125. Should have been:
if 100 >= percent_full >= 80.1: #Green5 80-100%
and I'm not sure about line 90. What I am wanting there is that the keg is either below 1% or above 102%
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