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nordic,nrf-twi

Vendor: Nordic Semiconductor

Description

These nodes are “i2c” bus nodes.

Nordic nRF family TWI (TWI master).

This binding can be used for nodes which can represent TWI
peripherals. When a single SoC peripheral ID corresponds to multiple
I2C peripherals (like TWI or TWIM), the corresponding devicetree
nodes must be set up to select TWI before use.

To select TWI, set the node's "compatible" to "nordic,nrf-twi" and
its "status" to "okay", e.g. using an overlay file like this:

    /* This is for TWI0 -- change to "i2c1" for TWI1. */
    &i2c0 {
            compatible = "nordic,nrf-twi";
            status = "okay";
            /* other property settings can go here */
    };

You can use either of these options to check TWI availability on
your SoC:

    1. Check the peripheral Instantiation table in the Memory
       section of your SoC's Product Specification document.
       A "TWI0" instance in the table means "i2c0" in the devicetree
       can be used with this binding, and similarly for "TWI1".

    2. Open your SoC's .dtsi file and look for a node definition that
       documents TWI support, like this:

           i2c0: i2c@40003000 {
                   /*
                    * This i2c node can be TWI, [...].
                    */
                   ...
           };

 If your SoC only has TWIM and TWIS I2C peripherals, you cannot use
 this binding. See the "nordic,nrf-twim" binding instead.

Properties

Properties not inherited from the base binding file.

Name

Type

Details

sda-pin

int

The SDA pin to use.

For pins P0.0 through P0.31, use the pin number. For example,
to use P0.16 for SDA, set:

    sda-pin = <16>;

For pins P1.0 through P1.31, add 32 to the pin number. For
example, to use P1.2 for SDA, set:

    sda-pin = <34>;  /* 32 + 2 */

This property is required.

scl-pin

int

The SCL pin to use. The pin numbering scheme is the same as
the sda-pin property's.

This property is required.

clock-frequency

int

Initial clock frequency in Hz