Colibri imx6ULL and Iris Carrier - ADC problems

Hi @martin_mig ,

Thanks for the detailed information!

If you are trying to use the sysfs (echo 1 > /sys/bus/iio/devices/iio:device0/buffer/enable), the issue may be related to the lack of IIO trigger support on the kernel, to make it work you need to recompile the kernel adding the flag CONFIG_IIO_SYSFS_TRIGGER. You can find information on how to do it on this article.

After booting the new kernel with the flag enabled, you need to create the trigger using the following commands:

echo 0 > /sys/bus/iio/devices/iio_sysfs_trigger/add_trigger 
cat /sys/bus/iio/devices/trigger0/name > /sys/bus/iio/devices/iio:device0/trigger/current_trigger

With this, you now can follow the instructions provided here to enable the continuous mode:

echo 1 > /sys/bus/iio/devices/iio\:device0/scan_elements/in_voltage0_en 
echo 100 > /sys/bus/iio/devices/iio\:device0/buffer/length 
echo 1 > /sys/bus/iio/devices/iio\:device0/buffer/enable

In the end, you can read the buffer data using the following command:

hexdump -e '"iio0 :" 8/2 "%04x " "\n"' /dev/iio:device0

Please let me know if it works for you or if you need any help from us.

Best regards,
Daniel Morais

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