mpibpc-mroose / hx711 Goto Github PK

• HX711 version: sparkfun (https://www.sparkfun.com/products/13879)
• Python version: 3.7
• Operating System: Raspbian Buster Lite Version:February 2020 Release date:2020-02-05 Kernel version:4.19

Description

I tried to use your library but am seemingly unable to connect to the hardware for some reason. When trying to run the example I get the following (repeatingly):

WARNING:root:setting gain and channel took more than 60µs. Time elapsed: 0.00006646

What I Did

Ran this code:

#!/usr/bin/python3
from hx711 import HX711
from RPi import GPIO
try:
    hx711 = HX711(
        dout_pin=5,
        pd_sck_pin=6,
        channel='A',
        gain=64
    )

    hx711.reset()   # Before we start, reset the HX711 (not obligate)
    measures = hx711.get_raw_data(num_measures=3)
finally:
    GPIO.cleanup()  # always do a GPIO cleanup in your scripts!

print("\n".join(measures))**

I have a sparkfun edition of the hx711. I connected the DAT pin to GPIO 5 and the CLK pin to GPIO 6. I have a raspberry pi model 3 b+. The VCC is connected to 5v pin.

Anything obvious I'm doing wrong?

• HX711 version: https://www.amazon.com/gp/product/B010FG9RXO/ref=ppx_yo_dt_b_asin_title_o04_s01?ie=UTF8&psc=1
• Python version: 3.7.6
• Operating System: balenalib/raspberrypi3-python:3.7.6

Description

Hi there. I am trying to us your library to take measurements from two load cells. I can either try to use two of the HX711 boards or just use one with Channel A & B. I am trying to do the later and only use one board with two channels. Can you let me know what I am doing wrong below. I am running the below code in it own thread outputting global measurements to the other threads. I keep getting this error:
WARNING:root:current channel != "A" so no need to set a gain current channel is 'B'
RIGHT RAW MEAN DATA: -45.19999999999982
LEFT RAW MEAN DATA: 357.59999999999854

What I Did

Here is my code:

'#!/usr/bin/python3
from future import print_function
import time
import threading
from hx711 import HX711
import RPi.GPIO as GPIO
import statistics

GPIO.setmode(GPIO.BCM)
left_calibration = 23380 # To try to calibrate each side to a TARE zero
right_calibration = 3390 # To try to calibrate each side to a TARE zero

def loadSensorBoth():
global left_pressure
global right_pressure
while True:
try:
DataPin = 5
ClockPin = 6
NumReadings = 10
print('READING HX711 LEFT')
hxleft = HX711(dout_pin=5, pd_sck_pin=6, channel="A")
print('LEFT RESET')
resultleft = hxleft.reset()
if resultleft:
print('LEFT READY TO USE')
else:
print("LEFT NOT READY")
left_pressure = ((statistics.mean(hxleft.get_raw_data(NumReadings))) - left_calibration)
if left_pressure != False:
print('LEFT RAW MEAN DATA: ' + str(left_pressure))
else:
print('LEFT INVALID DATA')
GPIO.cleanup()
print('READING HX711 RIGHT')
hxright = HX711(dout_pin=5, pd_sck_pin=6, channel="B")
print('RESET RIGHT')
resultright = hxright.reset()
if resultright:
print('RIGHT READY TO USE')
else:
print("RIGHT NOT READY")
right_pressure = ((statistics.mean(hxright.get_raw_data(NumReadings))) - right_calibration)
if right_pressure != False:
print('RIGHT RAW MEAN DATA: ' + str(right_pressure))
else:
print('RIGHT INVALID DATA')
GPIO.cleanup()
except (KeyboardInterrupt, SystemExit):
print('BYE')
finally:
GPIO.cleanup()`

• HX711 version: 1.1.2.2
• Python version: 3.5.3
• Operating System: Raspbian Stretch Lite June 2018

Description

The library blocks if there is no HX711 present. This seems to boil down to a couple of problems:

1. Creating the initial HX711 object will return a valid object even if there is no HX711 connected to the pins.
2. The reset() method blocks and does not throw an error if the _set_channel_gain() fails. It will log the warning "WARNING:root:setting gain and channel took more than 60µs" until Python itself throws a "RecursionError: maximum recursion depth exceeded in comparison"

It would be useful for the library to throw errors so that a failed HX711 (for whatever reason) can be detected and handled in some way, rather than simply crashing the application.

What I Did

I used the simple example code, but without an HX711 attached. This was to simulate a device with a connected HX711 based scale, where the scale is not plugged in to the main device.

...
WARNING:root:setting gain and channel took more than 60µs. Time elapsed: 0.0001909989950945601
WARNING:root:setting gain and channel took more than 60µs. Time elapsed: 0.00026499800151214004
--- Logging error ---
Traceback (most recent call last):
  File "/usr/lib/python3.5/logging/__init__.py", line 981, in emit
    msg = self.format(record)
  File "/usr/lib/python3.5/logging/__init__.py", line 831, in format
    return fmt.format(record)
  File "/usr/lib/python3.5/logging/__init__.py", line 569, in format
    if self.usesTime():
  File "/usr/lib/python3.5/logging/__init__.py", line 537, in usesTime
    return self._style.usesTime()
  File "/usr/lib/python3.5/logging/__init__.py", line 381, in usesTime
    return self._fmt.find(self.asctime_search) >= 0
RecursionError: maximum recursion depth exceeded in comparison

• HX711 version:
• Python version:
• Operating System:
  Buster - Raspberry pi 4

Description

I am using the example. As soon as the print message "Reset HX711" is printed, the Raspberry Pi shutdown. This happens if I don't have any device connected or not.

What I Did

Paste the command(s) you ran and the output.
If there was a crash, please include the traceback here.