Hello, how's it goin'?
I'm building an automatic counting scale using 4x 50kg load cells in a Wheatstone bridge configuration and connected into an HX711 amplifier, which then connects into my Arduino Uno through digital pins 4 and 5. Along with the HX711 the Arduino is also connected to a 16x2 LCD display, 3 LEDs, 2 pushbuttons, and a potentiometer. The issue seems to be hardware related, but I can share the source code if needed (it's a mess though, but it works as intended whenever I'm just using the HX711 and LCD display).
So here's the issue: I was hoping to use either a push button or a potentiometer to determine how many products would be measured by the scale. I settled on a middle ground and am using the potentiometer as the selector and the push button (with a software interrupt) as a confirmation button. Tare is then performed a few seconds after the press of the button. The issue seems to be that, when both are connected in parallel with the HX711 board the readings get a little bit crazy. Without anything connected the scale's readings oscillate a bit but that's expected as the load cells have a precision/accuracy rating of +/- 25g. Whenever they are connected though the HX711 can display inaccurate readings (sometimes up to +/- 100g in the span of a few seconds). I've attached the schematics of the circuit (the website didn't really have an HX711 module though, so I've used a breadboard to illustrate and attached another picture of that configuration), demonstrating how all the components are connected in -what I assume is- parallel. Are my worries justified or should I look for other sources of inaccuracy in the system?