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pythonweatherraspberry-pi4raspberry-pi-zero

Logging rainfall with Python


First post and I am at a dead end with this problem.

(some background) I have a raspberry PiZero which I am developing a weather station with, so far it logs temp, humidity and pressure as well as sending the data to the windy.com API. Recently I added a tipping bucket rain gauge. This has 2 wires which connect to the GPIO, when the bucket tips it momentarily competes the circuit, essentially a button press!

The goal here is to count the tips every hour, then reset. before resetting, send this data to log file + Windy API. This is the part I am struggling with.

I am pretty good with python but I am at a true writers block moment, here is a small program I cobbled together from snippets which counts the tips for testing

/usr/bin/python3
import requests
from gpiozero import Button
import time

rain_sensor = Button(27)
bucket_size = 0.2794
count = 0

    def bucket_tipped():
    global count
    count = count + 1
    print(count * bucket_size)

def reset_rainfall():
    global count
    count = 0


#display and log results
def timed_loop():
reset_rainfall
timeout = time.monotonic() + 3600   # 1 hour from now
while True:
    if time.monotonic() > timeout:  # break if timeout time is reached
        rain_sensor.when_pressed = bucket_tipped
        time.sleep(1)          # Short sleep so loop can be interupted
        continue
print count


  # close the log file and exit nicely
 GPIO.cleanup()

Solution

  • It looks like you are continuously setting your rain to 0 in your while True: loop.

    Edit: Try something like this for your loop.

    def timed_loop():
        rain = 0
        timeout = time.monotonic() + 3600   # 1 hour from now
        while True:
            if time.monotonic() > timeout:  # break if timeout time is reached
                # You place your code here that you want to run every hour. 
                # After that the loop restarts
                rain = 1  
                time.sleep(1)          # Short sleep so loop can be interupted
                continue
    

    Edit 3:

    With the following code you can record button presses over a specified amount of time.

    import time
    
    def bucket_tip_counter():
        recording_time_timeout = 3600  # Amount of seconds you want to have the timer run
        recording_time = time.monotonic() + recording_time_timeout
        button_timeout = 1  # This timeout is here so the button doesnt trigger the count more then once for each trigger
                            # You have to modify this to your needs. If the button stays activated for a few seconds you need to set the timer accordingly.
        count = 0           # Sets the counter to 0 at the start
        button = 0          # Here you need to replace the 0 with the GPIO pin that returns True if the button is pressed
        while True:         # starts the loop
    
            if button:         # if button gets pressed/bucket tipped
                count += 1     # up count by one
                time.sleep(button_timeout)  # wait specified timeout to make sure button isnt pressed anymore
    
            if time.monotonic() > recording_time:  # If the recording_time is reached the loop triggers this if condition
                print(count)   # print count
                               # Here you can also place code that you want to run when the hour is over
                               # Note that the counter wont start back up until that code is finished.
    
                count = 0      # set count back to 0
                recording_time = time.monotonic() + recording_time_timeout  # Set a new timer so the hour can start anew
                continue   # restart the loop
    
            time.sleep(1)  # small sleep to stop CPU hogging.