Analog input sampling rate

[bistv...@gmail.com]

  Dear Community,

 could anyone tell me at what rate the 8 analog inputs of the board can be sampled?

 I found this: http://beaglebone.cameon.net/home/reading-the-analog-inputs-adc   --- but 125ns per channel are hard to believe (this would be 8MHz). 

  I am a beginner, so I would use the analogRead command... 

  Ideas? Suggestions?

Thank you!

[TJF]

Only 7 input pins (AIN-[0-6]) are connected to header pins. AIN-7 is hard connected to the power supply on the board.

I don't know what you mean by analogRead command. The TSC_ADC_SS can sample 8 channels at 200 kHz. You can sample at that speed by using libpruio (bindings for C and FreeBASIC are available).

BR

[Istvan Biro]

   Hello,

 

Using libpruio,

may I ask if there is any support for reading an I2C sensor via the PRU – or any suggestion on how this can be done? The idea is to read an I2C accelerometer in determined intevals, using the PRU, at 1kHz +.

 

  Thanks a lot!

 

Best regards,

Istvan

[TJF]

Hi Istvan!

There's no I2C support in libpruio and it isn't planed to get implemented, sorry.

1 kHz should be possible to realize on ARM. (For hard real-time requirements use the second PRU.)

Regards