Hi Matti, Would you please provide details on which dts entries (or maybe a link to the entire dts file!) you're specifying in order to get ADC working with 3.18?
Thanks! On Monday, March 2, 2015 at 1:04:39 PM UTC-5, mala...@elisanet.fi wrote: > > > > On Thursday, February 26, 2015 at 5:18:51 PM UTC+2, dajia...@gmail.com > wrote: >> >> Hi, >> >> How come in my system, there is no /sys/bus/iio/devices/iio:device0? >> Under /sys/bus/iio/devices/, there is only one file iio_sysfs_trigger, >> which is a symbolic link to some other directory. >> Is there any configuration I need to do? >> I am using the latest BB black Rev C by Element14. It is OS is >> 3.8.13-bone47. >> >> Thx. >> > > Hi, > > You need to enable the ADC either by enabling the correct "cape" with > capemgr (only in kernel 3.8.*, see e.g. > http://hipstercircuits.com/reading-analog-adc-values-on-beaglebone-black/), > or by enabling it in the .dts-file (later kernels, such as the 3.18.4 which > I'm using). > > Matti > > >> >> On Wednesday, February 25, 2015 at 8:36:18 PM UTC+8, mala...@elisanet.fi >> wrote: >>> >>> Thanks for the suggestion. I'll keep that in mind if I need higher >>> sampling rates. However, I did find a way to read ADC through IIO so that >>> it doesn't hang. >>> >>> First set up the channels and the buffer through sysfs: >>> >>> echo 1 > /sys/bus/iio/devices/iio\:device0/scan_elements/in_voltage0_en >>> echo 256 > /sys/bus/iio/devices/iio\:device0/buffer/length >>> echo 1 > /sys/bus/iio/devices/iio\:device0/buffer/enable >>> >>> and then read from /dev/iio:device0. This way I can achieve about 8 kHz >>> sampling rate with a single channel, 4 kHz with two channels and down to >>> ~300 Hz with all eight channels. >>> >> -- 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.
