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      • PMW3610 Optical Mouse Sensor

      PMW3610 is a low‑power optical mouse sensor.

      Note
      • Currently, only implemented for nRF52 and RP2040 with a single-wire (SDIO) half-duplex SPI.
      • Set motion pin for better power efficiency. If omitted, the sensor is polled.
      • By default, report rate is limited to 125 Hz to prevent flooding the event channel, which causes latency issues especially over BLE. :::

      toml configuration

      ::: warning spi.mosi and spi.miso must be the same pin, or one of them empty.

      [[input_device.pmw3610]]
name = "trackball0"
id = 0 # optional number between 0-255. Ids are used for debug prints. Set to 0 if omitted.

spi.instance = "bitbang0"
spi.sck = "P0_05"
spi.mosi = "P0_04"
spi.miso = "P0_04"
spi.cs = "P0_09"
# or spi = { instance = "bitbang0", sck = "P0_05", mosi = "P0_04", miso = "P0_04", cs = "P0_09" }

motion = "P0_02" # Optional. If omitted, the sensor is polled.

report_hz = 125 # Optional: Report rate in Hz

force_awake = false
smart_mode = true
cpi = 800
# invert / swap axis on a sensor level
invert_x = true
# invert_y = true
# swap_xy = true
# invert / swap axis in software (in PointingProcessor)
# proc_invert_x = true
# proc_invert_y = true
# proc_swap_xy = true

      Split

      To add the sensor to the central or peripheral use

      [[split.central.input_device.pmw3610]]
name = ...

# resp.
[[split.peripheral.input_device.pmw3610]]
name = ...
      Multi-device ID assignment

      PointingEvent carries a device_id so that each PointingProcessor can be paired with a specific sensor. If you have sensors on both halves of a split keyboard, assign distinct ids to avoid the central treating them as the same device:

      # Central side sensor
[[split.central.input_device.pmw3610]]
id = 0

# Peripheral side sensor
[[split.peripheral.input_device.pmw3610]]
id = 1

      The peripheral forwards events to the central with the device_id preserved. The generated PointingProcessorConfig on the central will automatically use the matching device_id for each sensor.

      Breaking change

      Adding device_id to PointingEvent changes the serialized binary format used by the split protocol. Both halves of a split keyboard must be flashed with the same firmware version at the same time.

      Rust configuration

      Define a PointingDevice and add it to run_all! macro. For a split keyboard this must be added to the file (central.rs or peripheral.rs) corresponding to the side the sensor is connected to.

      use embassy_rp::gpio::{Output, Flex, Level};
use rmk::input_device::pmw3610::{BitBangSpiBus, Pmw3610, Pmw3610Config};
use rmk::input_device::pointing::PointingDevice;

let pmw3610_config = Pmw3610Config {
    res_cpi: 800,
    // force_awake: true,
    smart_mode: true,
    swap_xy: true,
    // invert_x: true,
    // invert_y: true,
    ..Default::default()
};

let pmw3610_sck = Output::new(p.P0_05, Level::High, OutputDrive::Standard);
let pmw3610_sdio = Flex::new(p.P0_04);
let pmw3610_cs = Output::new(p.P0_09, Level::High, OutputDrive::Standard);
let pmw3610_motion = Some(Input::new(p.P0_02, Pull::Up));
// or if you want to omit the motion pin:
// let pmw3610_motion = Option::<Input<'static>>::None;

let pmw3610_spi = BitBangSpiBus::new(pmw3610_sck, pmw3610_sdio);

const POINTING_DEV_ID: u8 = 0; // this ID can be anything from 0-255. Just make sure you don't use the same number twice for different sensors to avoid confusion.
let mut pmw3610_device = PointingDevice::<Pmw3610<_, _, _>>::new(
    POINTING_DEV_ID,
    pmw3610_spi,
    pmw3610_cs,
    pmw3610_motion,
    pmw3610_config,
);

// If you want to customize the report rate (Hz):
// let mut pmw3610_device = PointingDevice::<Pmw3610<_, _, _>>::with_report_hz(
//     POINTING_DEV_ID,
//     pmw3610_spi,
//     pmw3610_cs,
//     pmw3610_motion,
//     pmw3610_config,
//     125,
// );

run_all!(matrix, pmw3610_device),

      And define a PointingProcessor and add it to run_all! macro to process the events.

      Warning

      This should be added to the central.rs-File even if the sensor is on split peripheral.

          use rmk::input_device::pointing::{ PointingProcessor, PointingProcessorConfig };

    let pmw3610_proc_config = PointingProcessorConfig {
        // invert_x: true, // invert axis if neccesary
        // invert_y: true,
        // swap_y: true,
        ..Default::default()
    };

    let mut pmw3360_processor = PointingProcessor::new(&keymap, pmw3610_proc_config);

run_all!(pmw3610_processor, /* other processors and devices */)

      Pointing Modes

      The PointingProcessor has four modes (Cursor, Scroll, Sniper, Caret) with per‑layer configuration. See the PointingProcessor page for all options.