SparkFun Forums

[jdp2163]

I am looking to monitor the raw capacitance measurements/output of a MPR121 breakout board so that I may more accurately set the threshold values. I have looked through the MPR121 c++ code and cannot find what variable that I would print in order to extract the raw data from the MPR121. I understand how to use Serial.print(), I just don't know what variable that I would print in order to access this data. It seems that the returned value is a 1 or 0 bit that gets compiled into the "touched" variable, but I would like to know if it is possible to get the raw data from this chip before the logic operators compare the threshold that I have set to the raw capacitance measurement. It seems possible that the serial communication from the RedBoard only returns the 1s and 0s of the touched variable and doesn't actually return the raw data values. If it was possible, doing this would allow me run a trial of touching the sensor, and then setting the threshold based on the capacitance change that is observed instead of randomly guessing what the threshold should be and doing guess/check.


thank you in advance for any guidance!

[jremington]

You will need to study the device data sheet, available here: https://www.sparkfun.com/datasheets/Com ... MPR121.pdf