I just built libiio, and tested iio_readdev iio:device0, and the sample rate is terrible. Just above 1ksps. Just for perspective, this 4-5 times slower than using sysfs with one-shot mode. Continuous mode through sysfs, I've gotten up to around 15ksps.
Using mmap() on /dev/mem/ . . . well lets just say it can keep up with using the PRU's with the ADC's in many cases . But not all. On Sat, Oct 10, 2015 at 7:12 AM, William Hermans <yyrk...@gmail.com> wrote: > Hi Nuno, > > Yeah, Rick and I both know about libiio. We've actually been talking back > and forth by direct email yesterday. I've been attempting to find more > information on how the sample etc are stored in the buffer. I have been > successful reading the buffer one sample at a time however. But the data in > the buffer is not how is explained in what little information I could find. > Which says something like 16bits data per channel, and optional 64bit time > stamp. Where the data values I'm seeing out of the buffer are 32bit values, > with 16bit data, and 3 bit id tag. > > I could not figure out if fast mode was enabled or not, until now. But > where can I find more information on that ? I would like to test it if > possible. I really like the whole idea of iio, but it seems maintainers > have been coming and going. So finding good information on it is not easy, > and what can be found may, or may not apply to the current state of iio . . > . > > $ uname -r > 4.1.9-bone-rt-r16 > > $ lsb_release -a > No LSB modules are available. > Distributor ID: Debian > Description: Debian GNU/Linux 7.8 (wheezy) > Release: 7.8 > Codename: wheezy > > $ lsmod |grep industrialio > industrialio 41756 2 ti_am335x_adc,kfifo_buf > > The first time I've noticed kfifo_buf was last night and was curious . . . > > > On Sat, Oct 10, 2015 at 6:28 AM, Nuno Sucena Almeida <n...@aeminium.org> > wrote: > >> On 10/08/2015 10:06 PM, Rick Mann wrote: >> > What would it take to get libiio: >> > >> > >> https://wiki.analog.com/resources/tools-software/linux-software/libiio >> > >> > Into the BBB kernels? I think this would be amazing. >> >> Hi Rick, >> >> the linux kernel supports IIO (industrial input output) for quite some >> time and the BBB ADC has a IIO driver. You will have to enable the ADC >> pins in the device tree. >> >> I just started using the libiio on the BBB to read all 8 ADC channels. I >> initially tried it with the latest 4.2.x-bone linux kernel, but ran into >> issues enabling buffer continuous mode, so reverted back to 4.1.5-ti-r10 >> (ubuntu 15.10). Didn't investigate further what makes it different, will >> do whenever have the opportunity. >> >> I'm also investigating the low sample rates I'm getting...when creating >> the buffer the library complains: "WARNING: High-speed mode not >> enabled". The full source code is available and the documentation has >> reasonable quality, so it's just a matter of putting some time and >> effort improving it. >> >> Just for reference, here's the list of loaded modules after enabling the >> ADC through the device tree: >> >> ~$ lsmod >> Module Size Used by >> ti_am335x_adc 5984 0 >> kfifo_buf 3524 1 ti_am335x_adc >> industrialio 52301 2 ti_am335x_adc,kfifo_buf >> omap_rng 5254 0 >> rng_core 8737 1 omap_rng >> ti_am335x_tsc 6048 0 >> ti_am335x_tscadc 6199 2 ti_am335x_adc,ti_am335x_tsc >> uio_pdrv_genirq 3745 0 >> uio 10395 1 uio_pdrv_genirq >> tilcdc 32944 0 >> >> ~$ uname -r >> 4.1.5-ti-r10 >> >> ~$ lsb_release -a >> No LSB modules are available. >> Distributor ID: Ubuntu >> Description: Ubuntu Wily Werewolf (development branch) >> Release: 15.10 >> Codename: wily >> >> regards, >> Nuno >> >> -- >> >> -- >> 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 beagleboard+unsubscr...@googlegroups.com. >> 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
