Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector
Extension
[no extension]
Size
1425 bytes
Lines
40
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: Documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

What:		/sys/bus/iio/devices/iio:deviceX/in_altvoltageY_invert
Date:		October 2016
KernelVersion:	4.9
Contact:	Peter Rosin <peda@axentia.se>
Description:
		The DAC is used to find the peak level of an alternating
		voltage input signal by a binary search using the output
		of a comparator wired to an interrupt pin. Like so::

		                           _
		                          | \
		     input +------>-------|+ \
		                          |   \
		            .-------.     |    }---.
		            |       |     |   /    |
		            |    dac|-->--|- /     |
		            |       |     |_/      |
		            |       |              |
		            |       |              |
		            |    irq|------<-------'
		            |       |
		            '-------'

		The boolean invert attribute (0/1) should be set when the
		input signal is centered around the maximum value of the
		dac instead of zero. The envelope detector will search
		from below in this case and will also invert the result.

		The edge/level of the interrupt is also switched to its
		opposite value.

What:		/sys/bus/iio/devices/iio:deviceX/in_altvoltageY_compare_interval
Date:		October 2016
KernelVersion:	4.9
Contact:	Peter Rosin <peda@axentia.se>
Description:
		Number of milliseconds to wait for the comparator in each
		step of the binary search for the input peak level. Needs
		to relate to the frequency of the input signal.

Annotation

Implementation Notes