Hi,
The only thing i changed, according to communicate with this adc, is that i read 16 bits on the PRUADC.p and TIME_CLOCK is 1 (12.5Mhz for SPIclock). I'm not an assembly expert, so i really can't figure out the problem.
I tried read the this adc from the SPI0 of BBB(using Derek Molloy exampels too
http://exploringbeaglebone.com/chapter18/) , of course not with a 500kHz sampling, just for test, but the problem is the same, i'm working on this for more than 4 weeks, and i can't solve the problem, and is not a hardware problem.
In this examples, i have in the analog input of the adc, a square wave(3.3 V), and 3 constantes voltages(680mV,1.8V,3.3V), all examples done on PRU, and this are the results:
- Y axis -> Volts
- X axis -> Number of sample
- Vref of the adc is 4V.
Any help would be aprecciated.
Best Regards,
David