The IIO ADC driver can run at 800K samples per second. Here is the patch that made that possible.
https://patchwork.kernel.org/patch/9391487/ I can confirm that I have tested the driver at 800Ksps and it works fine as long as you have a proper low impedance source for each ADC channel. CPU utilization was about 5% if I recall and that was probably used by the iiod daemon, which I used to display the waveform on a remote Linux app. There is example code in the original Starterware for McSPI, which should work fine if you are using the PRU low level drivers. Regards, John > On Feb 26, 2018, at 12:56 PM, [email protected] wrote: > > Thanks John, > > I am now working with the starterware_PRU but i did not find examples for > using the McSPI with the PRU, do you think it will be hard to adapt the > initial code to the PRU ? > By the way, looking to the IIO driver documentation, it seems that for the > AM335x chip the max sampling rate is only 200k samples per second which may > not be enough : > http://processors.wiki.ti.com/index.php/Linux_Core_ADC_Users_Guide ; am I > right ? > > > Thanks > > Pierrick > > Le lundi 19 février 2018 23:15:50 UTC-5, john3909 a écrit : > Like I said, it was based on Starterware, so search Github for starterware > and you will see a project starterware_PRU. It does use the mcspi, so it is > not a bitbang implementation. > > Regards, > John > > > > >> On Feb 19, 2018, at 7:33 PM, [email protected] <> wrote: >> >> Thanks John for you answer, I was quit busy last week so I worked on this >> during the Weekend. >> >> Unfortunately, I was not able to find a project that is using the SPI and >> I2C interface with the PRU, I only found this one : >> https://github.com/chanakya-vc/PRU-I2C_SPI_master/wiki/SPI-Master-Controller >> <https://github.com/chanakya-vc/PRU-I2C_SPI_master/wiki/SPI-Master-Controller> >> >> But it is using bit banging for the SPI part and not using the on-board >> pull-up resistors for the I2C part. >> >> Concerning the ADC, I'll have a loook at the UIIO drivers in the coming days >> it seems that it meets my need in term of real-time acquisition. >> >> Regards, >> >> Pierrick >> >> -- >> For more options, visit http://beagleboard.org/discuss >> <http://beagleboard.org/discuss> >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/beagleboard/74949832-b67c-430f-811e-f3b2fff83852%40googlegroups.com >> >> <https://groups.google.com/d/msgid/beagleboard/74949832-b67c-430f-811e-f3b2fff83852%40googlegroups.com?utm_medium=email&utm_source=footer>. >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. > > > -- > For more options, visit http://beagleboard.org/discuss > <http://beagleboard.org/discuss> > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/3dc611e5-04e7-45bb-87d4-3c21a5665cec%40googlegroups.com > > <https://groups.google.com/d/msgid/beagleboard/3dc611e5-04e7-45bb-87d4-3c21a5665cec%40googlegroups.com?utm_medium=email&utm_source=footer>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/14F65A4F-6A27-48D2-83CA-A61E2EEB833B%40gmail.com. For more options, visit https://groups.google.com/d/optout.
