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Hello

I am using HX710 ADC for reading a load cell.

The HX711 is a serial device which outputs 24 bits in form of bit banging.

The data is in 2's complements form.

Vref = 5v

Full scale differential

input voltage range V(inp)-V(inn) ±0.0039*VREF mV

Internal gain = 128

Output data coding 2’s complement 800000 to 7FFFFF HEX

My problem is understanding this format.

I have always known in my MCU that a 10-bit sends 0-1023 bits and i can easily scale for a 0-5v input.

In this particular setup i have a loadcell giving a 0-10mv (2mV/V @ 5v excitation for a 5kg weight)

I don't need bipolar readings.

After i get the data as 24 bits (shifted appropriately) i XOR it with 0x80000

My question :

Since i am not interested in negative values, how do i scale this as normal decimal value for arithmetic calculations?

Learned members, please guide

Best regards

I am using HX710 ADC for reading a load cell.

The HX711 is a serial device which outputs 24 bits in form of bit banging.

The data is in 2's complements form.

Vref = 5v

Full scale differential

input voltage range V(inp)-V(inn) ±0.0039*VREF mV

Internal gain = 128

Output data coding 2’s complement 800000 to 7FFFFF HEX

My problem is understanding this format.

I have always known in my MCU that a 10-bit sends 0-1023 bits and i can easily scale for a 0-5v input.

In this particular setup i have a loadcell giving a 0-10mv (2mV/V @ 5v excitation for a 5kg weight)

I don't need bipolar readings.

After i get the data as 24 bits (shifted appropriately) i XOR it with 0x80000

Code:

`weight_raw ^= 0x800000;`

Since i am not interested in negative values, how do i scale this as normal decimal value for arithmetic calculations?

Learned members, please guide

Best regards