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Topic: Load Cell Datalogging at 80 Hz with a HX711  (Read 555 times) previous topic - next topic

Bencil88

Can anyone help me out? I'm trying to log loadcell data using a hx711 at 80 Hz. I am using this library https://github.com/bogde/HX711 and am logging the data with gobetwino.

I'm using the sample code from the library and I can't see how to increase measurments from 10 Hz to 80 Hz which should be possible according to the hx711 data sheet.

I'm also finding that when I look at the data I've collected measurements start at 10 Hz and slowly drop to 2 or 3 Hz over a period of ~ 4 mins. 

Any help much appreciated! I'm very new to this

Bencil88

Still not had any success getting this to work  >:(

Any ideas?

knut_ny

#2
Mar 27, 2017, 12:53 pm Last Edit: Mar 27, 2017, 12:55 pm by knut_ny
Get control of pin 15 on the HX-chip. Force it high for 80Hz (low fo 10Hz)
.. so this is part of design of the breakout board.

break the connection ti gnd and join pin 15 to pin 16 (Ucc)
Ny

nickcinquino

Hi Bencil88,
I can confirm that Knut-ny's method will work perfect...I desoldered pin 15 of the HX711
and jumpered to Vcc to get the sample rate to 80Sa/sec, for a model rocket motor test stand.
You can see the modification made to the module board in this short vid:

https://www.youtube.com/watch?v=bvfiEOoaTNY

Bencil88

Thanks to both of you, that's really helpful.

Sounds like this may test my soldering skills though!


Bencil88

#5
Apr 22, 2017, 10:22 am Last Edit: Apr 22, 2017, 10:28 am by Bencil88
For the benefit for any noobs like myself wanting to do 80 Hz data logging with a hx711 breakout...

knut_ny's method worked great. Desolder pin 15 and lever it up so parallel to the board then put a blob of solder linking to pin 16, see pic below.

For saving data on the computer I swapped from gobetwino to CoolTerm which seems to be fine at 80Hz, where as gobetwino had some issues. CoolTerm is a bit easier to use too.

Thanks y'all

https://drive.google.com/open?id=0B2jcKTdVw-kVdGtXS280ZjRFTDQ

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