What determines the sampling frequency of BBB

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1

Hi guys,

We are currently preparing to start a oscilloscope project using beaglebone black.

I have one question, what determines the sampling rate of the oscilloscope, ADC is one,so to overcome its low sampling, am thinking to use external ADC, what else?

Thanks

2

Hi!

What do you mean by “its low sampling”?

The TSC_ADC_SS can sample at 200 kHz.

BR

3

For an oscilloscope this is quite slow. how about using PRU ADC sampling?

4

Agree, 200KHz is abit too slow, we are looking at >10MHz, am thinking in the same line using PRU ADC, but not sure how to achieve the high frequency by using PRU ADC.the sampling frequency of PRU ADC is determined by ADC only? Any other factors will affect? Or there is any better way?Thanks

5

PRU is running at 200 MHz, when you plan to have sample rates of more than 10 MHz you will have to do the whole ADC sampling of one frame in less than 20 clock cycles/with less than 20 instructions. Sounds like you have to do that with highly optimised PRU-ASM-code … and I’m not sure if this will fit…