ADS1013: bad read data

Adam,


I can only think of a couple of things that might be an issue.

First, the ADS1013 is a differential input and measures the input voltage from AIN0 to AIN1. It doesn't make single-ended measurents from either AIN0 or AIN1 to GND. For single-ended measurement from any individual input to GND, you would need to use the ADS1015. Reading your post, I wasn't sure if that was clear.

Second when the device first powers up, it starts in single-shot mode. To use the device, you need to start a single conversion by writing a 1 to the OS bit. Alternatively, you could put the device into continuous conversion mode to get it working. If you don't start up the device, I'm not sure what comes out of the conversion register.

If neither of these hints pan out, I'd make sure that you can read and write from the device correctly. I'd also get a scope shot of the SDA and SCL lines to make sure that there isn't something else affecting your I2C lines.


Joseph Wu

Joseph, thank for reply

I have connect AIN1 to GND and measuring AIN0 singal should give me voltage, according to documentation:
"The ADS1013 and ADS1014 can measure single-ended signals by connecting AIN1 to GND externally."

I start conversion. I send 1 (OS bit) to confing register. I have tried Continuous-conversion and Single-shot mode (MODE bit). (There is not much bits and possibilies in ADS1013.)

I2C is working ok, I can read for example conversion registers after porwe up and have 0x8583 each time.

Even I have connect AIN0 directly to power supply to sure proper voltage.

Adam