I'm doing a project of interfacing AD7730 with PIC16F877.
I am successfully communicating with internal registers of AD7730, but the problem is when I am going to read the data register it is showing only 0.
And RDY pin is not going to low, that to indicate new data is available.
Then I put some break points in codes and found that when I give the command to internal calibration, it is not performing.
Because if it is performing it should reset the Mode registry first three bits to 000, in my case all the time it is showing my last command only.
I used 5V for excitation and power-up the IC
ref+ and ref- are supplied same as VDD and VGND, and after voltage regulator 7805 , it is supplying 4.96V to those pins.
crystal oscillator for AD7730 is 4.952MHz ,and 15pF capacitors are fixed.
my load cell is 10mV full range with 5V excitation.
Procedure I used is
Write to the filter register first.
Then write to the Mode register for calibration.
Pls help me
adc_write_byte(2);//Mode Internal full scale calibration
This adc_write_byte function was developed by myself and by writing and after reading same registry I found that communication is perfectly working.