Load cell, i need help

hello everyone , I 'm doing a job for the college that I need to show on a dashboard the value of the load cell and an ldr , but the problem is that I can not show both at the same time on the dashborad since the load cell use two ports on the arduino ,
I saw that you have to use the function to write some codes but I have no idea, can someone help me please

Hello and welcome,

I think most people use MQTT for this, but there's probably a bunch of ways to do it. What is your plan so far?

Can you explain what you mean by that please?

hello in short, I need to show the LDR and load cell values ​​in a dashboard, for example in node-red we will create a dashboard to show the values ​​of ldr and load cell, but it is not possible to show both when at the same time, because the load cell has 4 wires, one wire is the VCC,
GND and the other two are the wires to put in the arduino to make the programming, but in node-red I can only select one of the wires, so I went to use the other method, using the node called "function" but I don't know write the code, sorry for any grammatical errors, i'm brazilian and i'm still learning english hahah

What do you get from the two wires that you want to show?

What Arduino board are you using? What inputs are you using for the load cell?

I am not familiar with all the Arduino boards, but from what I have seen the analog inputs are not sensitive enough to measure the output of a load cell directly. Normally there needs to be an amplifier between the load cell and the Arduino board.

This sounds like you are connecting the load cell directly to two of the analog inputs. If this is what you are doing, this will not give much sensitivity. The analog input range is from 0 volts to Vcc. The output of a load cell is only 10 mV (when using 5 volts) when fully loaded to the maximum weight the load cell is rated for.

The analog to digital converter for the Arduino is typically 10 bits, which gives a step size of approximately 5mV. (when using 5 volt for the processor)

An amplifier will increase the signal level so that a (one) analog input can measure the output. The also are special load cell amplifier boards that provide a digital interface. You can find more information at https://www.instructables.com/Arduino-Scale-With-5kg-Load-Cell-and-HX711-Amplifi/

The HX711 Load cell amplifier is the easiest way to interface to a load cell. Less commonly used by hobbyists is the linear amplifier method, as in the following.


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