errr oops, I sent too soon. mmap() is fast, and can actually read from the ADC faster than the ADC can update values. But, it's using the main processor to do so, and if you need to do more than just read the ADC. Additional processes would have to compete for processor time. So, if one does want / need to read at maximum speed, it might be wise to offload the main processor, by using a PRU.
It would not matter if this were done in userspace, or kernel space. It'll definitely put a load strain on the ARM processor. On Wed, Mar 2, 2016 at 3:19 PM, William Hermans <[email protected]> wrote: > *You realize that you can read the ADC from Linux at full speed also? No >> need to use the PRU. * >> *Regards,* >> > *John* > > I do, because I've proven just that :) *mmap()* is dahmed fast . . . > > > On Wed, Mar 2, 2016 at 2:32 PM, John Syne <[email protected]> wrote: > >> You realize that you can read the ADC from Linux at full speed also? No >> need to use the PRU. >> >> Regards, >> John >> >> >> >> >> On Mar 2, 2016, at 12:43 PM, TJF <[email protected]> wrote: >> >> Hello PatM001! >> >> There's libpruio <http://beagleboard.org/project/libpruio/>, which >> provides ADC sampling at full speed (200 kHz). You'll get rid of the >> exeptions (and the miss readings of the sysfs driver in case of sampling >> multiple channels). >> >> The downside: no C# binding yet. It's written in FreeBASIC/PASM and gets >> shipped with a C header. You may try SWIG <http://www.swig.org/> on the >> C header in order to generate a binding for your prefered language. >> >> If you try, please share your results, or at least report. >> >> BR >> >> -- >> 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]. >> For more options, visit 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]. >> For more options, visit 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]. For more options, visit https://groups.google.com/d/optout.
