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nordic,nrf-led-matrix

Vendor: Nordic Semiconductor

Description

Generic LED matrix driven by nRF SoC GPIOs

Properties

Properties not inherited from the base binding file.

Name

Type

Details

height

int

 
Height of the panel driven by the controller, with the units in pixels.

This property is required.

width

int

 
Width of the panel driven by the controller, with the units in pixels.

This property is required.

row-gpios

phandle-array

 
Array of GPIOs to be used as rows of the matrix.

This property is required.

col-gpios

phandle-array

 
Array of GPIOs to be used as columns of the matrix.

This property is required.

pixel-mapping

uint8-array

 
Array of bytes that specify which rows and columns of the matrix
control its particular pixels, line by line. Each byte in this
array corresponds to one pixel of the matrix and specifies the row
index in the high nibble and the column index in the low nibble.

For example, the following snippet (from the bbc_microbit board DTS):

  width = <5>;
  height = <5>;
  pixel-mapping = [00 13 01 14 02
                   23 24 25 26 27
                   ...

specifies that:
- pixel (0,0) is controlled by row 0 and column 0
- pixel (1,0) is controlled by row 1 and column 3
- pixel (0,1) is controlled by row 2 and column 3
- pixel (1,1) is controlled by row 2 and column 4
and so on.

This property is required.

refresh-frequency

int

 
Frequency of refreshing the matrix, in Hz.

This property is required.

timer

phandle

 
Reference to a TIMER instance for controlling refreshing of the matrix.

This property is required.

pwm

phandle

 
Reference to a PWM instance for generating pulse signals on column
GPIOs. If not provided, GPIOTE and PPI channels are allocated and
used instead for generating those pulses.

pixel-group-size

int

 
This value specifies the maximum number of LEDs in one row that can
be lit simultaneously.
If set to 1, only a single LED is turned on in a particular time slot.
Bigger values increase the maximum achievable brightness of the LEDs
and lower the CPU load by decreasing the frequency of execution of
the timer interrupt handler.
In case GPIOTE and PPI channels are used for generating the pixel pulse
signals, the number of channels that need to be allocated is equal to
this value.
If GPIOTE and PPI channels are used, the upper limit for the value is
defined by the number of CC channels in the used timer minus one.
If PWM is used, the upper limit is the number of PWM channels.

This property is required.