Module tsc

TSC Peripheral Interface

This module provides an interface for the Touch Sensing Controller (TSC) peripheral. It supports both blocking and async modes of operation, as well as different TSC versions (v1, v2, v3).

Key Concepts

• Pin Groups: TSC pins are organized into groups, each containing up to four IOs.
• Pin Roles: Each pin in a group can have a role: Channel, Sample, or Shield.
• Acquisition Banks: Used for efficient, repeated TSC acquisitions on specific sets of pins.

Example (stm32)

let device_config = embassy_stm32::Config::default();
let context = embassy_stm32::init(device_config);

let config = tsc::Config {
    ct_pulse_high_length: ChargeTransferPulseCycle::_4,
    ct_pulse_low_length: ChargeTransferPulseCycle::_4,
    spread_spectrum: false,
    spread_spectrum_deviation: SSDeviation::new(2).unwrap(),
    spread_spectrum_prescaler: false,
    pulse_generator_prescaler: PGPrescalerDivider::_16,
    max_count_value: MaxCount::_255,
    io_default_mode: false,
    synchro_pin_polarity: false,
    acquisition_mode: false,
    max_count_interrupt: false,
};

let mut g2: PinGroupWithRoles<embassy_stm32::peripherals::TSC, G2> = PinGroupWithRoles::new();
g2.set_io1::<tsc_pin_roles::Sample>(context.PB4);
let sensor_pin = g2.set_io2::<tsc_pin_roles::Channel>(context.PB5);

let pin_groups = PinGroups {
    g2: Some(g2.pin_group),
    ..Default::default()
};

let mut touch_controller = tsc::Tsc::new_blocking(
    context.TSC,
    pin_groups,
    config,
).unwrap();

let discharge_delay = 5; // ms

loop {
    touch_controller.set_active_channels_mask(sensor_pin.pin.into());
    touch_controller.start();
    touch_controller.poll_for_acquisition();
    touch_controller.discharge_io(true);
    Timer::after_millis(discharge_delay).await;

    match touch_controller.group_get_status(sensor_pin.pin.group()) {
        GroupStatus::Complete => {
            let group_val = touch_controller.group_get_value(sensor_pin.pin.group());
            // Process the touch value
            // ...
        }
        GroupStatus::Ongoing => {
            // Handle ongoing acquisition
            // ...
        }
    }
}

Async Usage

For async operation, use Tsc::new_async and pend_for_acquisition instead of polling.

Re-exports

• pub use acquisition_banks::*;
• pub use config::*;
• pub use errors::*;
• pub use io_pin::*;
• pub use pin_groups::*;
• pub use tsc::*;
• pub use types::*;

Modules

• acquisition_banks
  Structures and implementations for TSC acquisition banks.
• config
  Configuration structures and enums for the TSC peripheral.
• errors
  Error types and definitions for the TSC module.
• io_pin
  Definitions and implementations for individual TSC I/O pins.
• pin_groups
  Definitions and implementations for TSC pin groups.
• tsc
  Core implementation of the TSC (Touch Sensing Controller) driver.
• types
  Type definitions used throughout the TSC module.

Structs

• InterruptHandler
  TSC interrupt handler.

Enums

• Error
  Error type defined for TSC

Traits

• Instance
  TSC instance trait