I work on the AD7745/4AD77466 evaluation board. The software application from AD displays code CAP which represents the value of the capacitance in hexadecimal.I work with the single ended mode with no CAPDAC in first step. We will add a CAPDAC value in a second step.
I develop my own application where I read the CAP DATA registers to have the raw data.This raw data are different from Code CAP of the AD software application.I read all the datasheets on the AD7746 and his evaluation board datasheet too, but I can't find the right formula.1) What is the formula to have the Code CAP from the raw data(CAP DATA registers) ?2) I already have the formula for convert the value in hexadecimal in pF. So that is not my question.
Please help me I can't find any respond on it and I don't know why. I must have done something.
This raw data are different from Code CAP of the AD software application
Can you please clarify.?
The value of the 3 registers CAP DATA that I read w/ my own application accross the I2C bus (my microcontroller PIC32 as the master) is different of the value Code CAP displays on the software application AD7745-46EB.
Are you reading all the three bytes of CAP DATA before initiating the next conversion?
Raw data is [Cap Data H, Cap Data M, Cap Data L]
Also did you verify all the register settings in your program with that on the Eval software?
Thanks for your reply
Yes we are.Yes we put in our program the same register settings.
In that case, the raw data captured by Eval software and your application should remain same, provided all other conditions are same.