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help reading schemA...
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help reading schemATIC, i dont understand it and i need someone to break it down for me

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I hope you don't mind - I copied the image from Imgur ... for some odd reason I couldn't even load it without doing some extra effort.

So I'd start with making a bill of materials needed:

  • Load cell (I just learned that this converts weight/pressure to some readable, like this item)
  • a HX711 module (like this one)
  • I see two push buttons (default open, closes when pushing the button)
  • 2x 10 KOhm resistors
  • Arduino Uno
  • A piezo buzzer
  • a 16x2 LCD screen with I2C connections

I think the confusing part may be the display section. The "I2C" and the "LCD" can be bought as one single item, or as two items: a LCD screen and a I2C module.
More details can be found here: Arduino LCD I2C tutorial.

The load cell has 4 wires, and they go to the HX711 module:

LOAD CELL          HX711
Green (Sig +)  ->  A+
White (Sig -)  ->  A- 
Black (Exc -)  ->  E-
Red   (Exc +)  ->  E+


The HC711 module has 4 more pins to connect:

VCC             ->  +5 Volt
GND             ->  Ground (or minus)
CLK (or Clock)  ->  Arduino Pin 2
DT (or Data)    ->  Arduino Pin 3


The Arduino is has a push button and a resistor on the pins A0 and A1.
The buzzer goed on Pin 13 of the Arduino.
The I2C of the LCD is connected to Arduino Pin A4 (I2C pin: SDA) and Arduino A5 (I2C pin: SEL) of the Arduino.

Note: The Arduino will also need +5V and GND connected (the schematic is not showing this, which is not uncommon).
The LCD display needs +5V and GND as well of course.

Since this all is pretty obvious to me, tell me where you're getting stuck and I'll try to explain ... 😊 



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