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1What: /sys/bus/iio/devices/iio:deviceX/in_altvoltageY_invert2Date: October 20163KernelVersion: 4.94Contact: Peter Rosin <peda@axentia.se>5Description:6 The DAC is used to find the peak level of an alternating7 voltage input signal by a binary search using the output8 of a comparator wired to an interrupt pin. Like so::9 10 _11 | \12 input +------>-------|+ \13 | \14 .-------. | }---.15 | | | / |16 | dac|-->--|- / |17 | | |_/ |18 | | |19 | | |20 | irq|------<-------'21 | |22 '-------'23 24 The boolean invert attribute (0/1) should be set when the25 input signal is centered around the maximum value of the26 dac instead of zero. The envelope detector will search27 from below in this case and will also invert the result.28 29 The edge/level of the interrupt is also switched to its30 opposite value.31 32What: /sys/bus/iio/devices/iio:deviceX/in_altvoltageY_compare_interval33Date: October 201634KernelVersion: 4.935Contact: Peter Rosin <peda@axentia.se>36Description:37 Number of milliseconds to wait for the comparator in each38 step of the binary search for the input peak level. Needs39 to relate to the frequency of the input signal.40