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What: /sys/bus/iio/devices/iio:deviceX/in_count0_preset
KernelVersion: 4.13
Contact: fabrice.gasnier@st.com
Description:
Reading returns the current preset value. Writing sets the
preset value. Encoder counts continuously from 0 to preset
value, depending on direction (up/down).
What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
KernelVersion: 4.13
Contact: fabrice.gasnier@st.com
Description:
Reading returns the list possible quadrature modes.
What: /sys/bus/iio/devices/iio:deviceX/in_count0_quadrature_mode
KernelVersion: 4.13
Contact: fabrice.gasnier@st.com
Description:
Configure the device counter quadrature modes:
- non-quadrature:
Encoder IN1 input servers as the count input (up
direction).
- quadrature:
Encoder IN1 and IN2 inputs are mixed to get direction
and count.
What: /sys/bus/iio/devices/iio:deviceX/in_count_polarity_available
KernelVersion: 4.13
Contact: fabrice.gasnier@st.com
Description:
Reading returns the list possible active edges.
What: /sys/bus/iio/devices/iio:deviceX/in_count0_polarity
KernelVersion: 4.13
Contact: fabrice.gasnier@st.com
Description:
Configure the device encoder/counter active edge:
- rising-edge
- falling-edge
- both-edges
In non-quadrature mode, device counts up on active edge.
In quadrature mode, encoder counting scenarios are as follows:
+---------+----------+--------------------+--------------------+
| Active | Level on | IN1 signal | IN2 signal |
| edge | opposite +----------+---------+----------+---------+
| | signal | Rising | Falling | Rising | Falling |
+---------+----------+----------+---------+----------+---------+
| Rising | High -> | Down | - | Up | - |
| edge | Low -> | Up | - | Down | - |
+---------+----------+----------+---------+----------+---------+
| Falling | High -> | - | Up | - | Down |
| edge | Low -> | - | Down | - | Up |
+---------+----------+----------+---------+----------+---------+
| Both | High -> | Down | Up | Up | Down |
| edges | Low -> | Up | Down | Down | Up |
+---------+----------+----------+---------+----------+---------+
|
