SparkFun Forums

[awootton]

I have a beehive scale working beautifully with 4 load cells hooked up in parallel to an HX711 connected to an arduino (Sodaq Mbili). Now I want to set up a second scale on another hive to act as a control. It seems to me that I should be able to connect multiple HX711 amplifiers to the single arduino as there are multiple digital inputs available. So the question is what do I do with the other connections VCC, CLK and GND? Do I just connect these in parallel? Thanks for input.

[agilb]

I am also interested in doing this. I have multiple load cells and two of the hx711 boards, but would also love some advice on the next step. I did notice the other channel broken out, but don't want to use it because of the reduced resolution. Thanks in advance.

[Valen]

According to the datasheet, the clock line is also used to put the device to sleep (if held high long enough) and come out of it (pulled down). I guess you can share the clock line and ignore the Dout from the scales you are not interested in at that time. As they would all respond in time. If you want to get all the data at the same time you might need to do direct port manipulation (reading) to get all the Dout pins at the same time within 50 micro seconds. Depending on your coding skills doing multiple digital reads might take too long causing the HX711 to go into powerdown.

If you want different sampling parameters (gain) for each scale then you need to send different ammount of pulses to each. So then you need seperate clock lines. Sample rate is set by a jumper on this board, so by default is the same for all.

[aewal90253]

Good Morning,

Did you come up with a solution to connect multiple scales to one controller? I am interested in doing something similar, I was looking to use the OpenScale board to simplify things a little but i too want to take multiple scales and multiple DHT22 sensors and connect back to a Particle Electron board with Cellular connectivity. Ideally i would like to have one Particle board per bee yard and only put scales and sensors in each hive to cut down on costs.

Any information would be greatly appreciated.