On Friday, March 16, 2012 12:30:19 AM UTC, RogerN wrote:
I got an AD7730 IC (load cell analog to digital converter) and connected to

an Arduino microcontroller and a load cell. The AD7730 chip is only on a

solderless breadboard right now, but I'm getting pretty good results. The

load cell I'm using is rated for 30Kg's and I'm able to read 1/10th of a

gram with some noise & drift. So far my microcontroller code just

configures the AD7730 chip, reads raw values and converts them to units by

responding to computer keys for zero and calibration.



I'm wanting to get this thing all together in a handheld enclosure with

rechargeable batteries, a LCD display and buttons to allow setup,

configuration, and calibration. A connector will allow me to change load

cells so I can use this with a reloading scale or a 10 ton crane scale, with

all the configuration and calibration saved for each load cell I want to use

it for, saving data for a dozen load cells shouldn't be a problem.



Just thought I'd share this in case anyone wants to mess with Arduino scales

and the AD7730 chip, I can paste my Arduino code that will help get you

started. I couldn't find any functional code with my searches so I started

with a program that wasn't working and got it going with major

modifications.



RogerN

Hi Roger,

Realise this is an old post now, but if you have any code to hand would be much appreciated.

I have simple weigh scale setup going, and didn't have enough resolution with other chips. Working with the AD7730 now, and despite having finally got SPI working it seems to be really finicky. I often seem to end up in a loop of 1 to 4 bytes repeatedly sent back for whatever register I'm trying to read from... And it only seem correctly write to registers on startup about 70% of the time. The others it just returns spurious bytes.

Anything you've learned might be helpful

Thanks

David