Example: Reading HX711 ADC

[ccrause]

Prompted by this question regarding reading the HX711 ADC on Raspberry Pi, I thought it would be interesting to try this on an atmega328p (a.k.a. Arduino Uno).  Since I bought an HX711 board a few years ago "just in case", this was a good excuse to solder some wires to the board and give it a test.

Code can be viewed on Github.

[MarkMLl]

I think you might have been better appending that to the original thread.

OK, so it looks like that's bit-banging it rather than using e.g. SPI.

MarkMLl

[ccrause]

I think you might have been better appending that to the original thread.

That refers to Linux on RPi, AVR code is a bit different.  I will post a cross reference, then the OP can decide whether to look at this.

OK, so it looks like that's bit-banging it rather than using e.g. SPI.

It seemed easier to just start with bit-bang.  At least reading the 3 data bytes should be possible over SPI, but on AVR the last 1 - 3 clock pulses used to configure the next conversion would need to be bit-banged. Maybe I'll test SPI sometime this weekend.

[ccrause]

Code can be viewed on Github.

OK, so it looks like that's bit-banging it rather than using e.g. SPI.

Updated example so that a user can select between using bit-bang or SPI. Even using SPI to read the 3 data bytes, the configuration for the next conversion needs to be bit-banged because the SPI peripheral can only work with 8 bit chunks of data.

[MarkMLl]

the SPI peripheral can only work with 8 bit chunks of data.

Bring back the 8523 :-)

...of course, that wouldn't really do the job, but broadly speaking it had more support for weird protocols than anything else known to man. Although I have a very vague recollection of an '80s device which could do everything from PWM waveform synthesis to Ethernet.

MarkMLl