Analog input 'Tare/Zero' Weight Function

Gordon

Without seeing your code I can't offer the exact code but something along these lines should work.

Detect 'zero' button

Read analog and store in a variable (ie int ZeroValue = 0; // value to store zero reading)

Whenever you read the load cell, you subtract the ZeroValue from the reading

Detect the 'monitor' button

display or print the ZeroValue rather than the load cell reading

This will remain until the micro is reset, either by power, reset button or upload.

Good luck

Mark

Hi Mark,

Thank you for your early feedback, you described it exactly how I would do it in PLC terms, I am new to Arduino so I am struggling with the code structure, I feel your suggestion will work, I will need to trial a few sketches and then import the working code into my current project.

Best wishes,

Gordon

Hi Mark,

Thank you for your early feedback, you described it exactly how I would do it in PLC terms, I am new to Arduino so I am struggling with the code structure, I feel your suggestion will work, I will need to trial a few sketches and then import the working code into my current project.

Best wishes,

Gordon

int loadCellPin = 1;

int tareButtonPin = 8;

int currentWeight = 0;

int taredWeight = 0;

void loop() {

  //do some math to convert anaglogRead(loadCellPin) to a weight

  currentWeight = //results of that math;

  //check if the tare button is pushed, to see if it needs to store a value.

  if (digitalRead(tareButtonPin) == HIGH) {

    taredAmt = anaglogRead(loadCellPin);

  }

  //do the math to convert taredWeight from 0-1023 to a weight

  //i assume you'll have some sort of lcd code setup

  lcd.print("Weight: ");

  lcd.print(currentWeight - taredWeight);

}

This is what you need on a very basic level, but without any specifics I cant help too much more.

Hi,

Thanks for the assistance, I would like to send my code to you to check it over, I am only a beginner and it has been trial and error so far.

Basically I want to store a weight to an SD card shield which I have setup ok, but the tare function has stumped me!

I have 2 buttons, button 1 is the Tare/Zero, Button 2 is the 'take weigh sample' button.

I have setup to write to monitor and I can display the Tare weight when button 1 is pressed, when Button 2 is pressed it displays a scaled value in Pounds/Ounces, my problem is I cant get the subtraction of the Tare weight to work.

I would appreciate any help you could give me.

How can I send you the code?

Regards,

Gordon