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STM32-TSC: enable discriminating between pins within same TSC group and improve TSC library in general

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This commit is contained in:
michel
2024-08-07 21:58:49 +02:00
parent 1a1d5c4689
commit 721c6820d4
27 changed files with 3007 additions and 1438 deletions
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2
examples/stm32l0/.cargo/config.toml
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@@ -1,6 +1,6 @@
[target.'cfg(all(target_arch = "arm", target_os = "none"))']
# replace your chip as listed in `probe-rs chip list`
runner = "probe-rs run --chip STM32L053R8Tx"
runner = "probe-rs run --chip STM32L073RZTx"
[build]
target = "thumbv6m-none-eabi"

2
examples/stm32l0/Cargo.toml
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@@ -6,7 +6,7 @@ license = "MIT OR Apache-2.0"
[dependencies]
# Change stm32l072cz to your chip name, if necessary.
embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["defmt", "stm32l072cz", "unstable-pac", "time-driver-any", "exti", "memory-x"] }
embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["defmt", "stm32l073rz", "unstable-pac", "time-driver-any", "exti", "memory-x"] }
embassy-sync = { version = "0.6.1", path = "../../embassy-sync", features = ["defmt"] }
embassy-executor = { version = "0.6.3", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
embassy-time = { version = "0.3.2", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }

24
examples/stm32l0/README.md Normal file
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@@ -0,0 +1,24 @@
# Examples for STM32L0 family
Run individual examples with
```
cargo run --bin <module-name>
```
for example
```
cargo run --bin blinky
```
## Checklist before running examples
You might need to adjust `.cargo/config.toml`, `Cargo.toml` and possibly update pin numbers or peripherals to match the specific MCU or board you are using.
* [ ] Update .cargo/config.toml with the correct probe-rs command to use your specific MCU. For example for L073RZ it should be `probe-rs run --chip STM32L073RZTx`. (use `probe-rs chip list` to find your chip)
* [ ] Update Cargo.toml to have the correct `embassy-stm32` feature. For example for L073RZ it should be `stm32l073rz`. Look in the `Cargo.toml` file of the `embassy-stm32` project to find the correct feature flag for your chip.
* [ ] If your board has a special clock or power configuration, make sure that it is set up appropriately.
* [ ] If your board has different pin mapping, update any pin numbers or peripherals in the given example code to match your schematic
If you are unsure, please drop by the Embassy Matrix chat for support, and let us know:
* Which example you are trying to run
* Which chip and board you are using
Embassy Chat: https://matrix.to/#/#embassy-rs:matrix.org

122
examples/stm32l0/src/bin/async-tsc.rs
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@@ -1,122 +0,0 @@
// Example of async TSC (Touch Sensing Controller) that lights an LED when touch is detected.
//
// Suggested physical setup on STM32L073RZ Nucleo board:
// - Connect a 1000pF capacitor between pin A0 and GND. This is your sampling capacitor.
// - Connect one end of a 1K resistor to pin A1 and leave the other end loose.
// The loose end will act as touch sensor which will register your touch.
//
// Troubleshooting the setup:
// - If no touch seems to be registered, then try to disconnect the sampling capacitor from GND momentarily,
// now the led should light up. Next try using a different value for the sampling capacitor.
// Also experiment with increasing the values for `ct_pulse_high_length`, `ct_pulse_low_length`, `pulse_generator_prescaler`, `max_count_value` and `discharge_delay`.
//
// All configuration values and sampling capacitor value have been determined experimentally.
// Suitable configuration and discharge delay values are highly dependent on the value of the sample capacitor. For example, a shorter discharge delay can be used with smaller capacitor values.
//
#![no_std]
#![no_main]
use defmt::*;
use embassy_stm32::bind_interrupts;
use embassy_stm32::gpio::{Level, Output, Speed};
use embassy_stm32::tsc::{self, *};
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};
bind_interrupts!(struct Irqs {
TSC => InterruptHandler<embassy_stm32::peripherals::TSC>;
});
#[cortex_m_rt::exception]
unsafe fn HardFault(_: &cortex_m_rt::ExceptionFrame) -> ! {
cortex_m::peripheral::SCB::sys_reset();
}
/// This example is written for the nucleo-stm32l073rz, with a stm32l073rz chip.
///
/// Make sure you check/update the following (whether you use the L073RZ or another board):
///
/// * [ ] Update .cargo/config.toml with the correct `probe-rs run --chip STM32L073RZTx`chip name.
/// * [ ] Update Cargo.toml to have the correct `embassy-stm32` feature, for L073RZ it should be `stm32l073rz`.
/// * [ ] If your board has a special clock or power configuration, make sure that it is
/// set up appropriately.
/// * [ ] If your board has different pin mapping, update any pin numbers or peripherals
/// to match your schematic
///
/// If you are unsure, please drop by the Embassy Matrix chat for support, and let us know:
///
/// * Which example you are trying to run
/// * Which chip and board you are using
///
/// Embassy Chat: https://matrix.to/#/#embassy-rs:matrix.org
#[embassy_executor::main]
async fn main(_spawner: embassy_executor::Spawner) {
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,
channel_ios: TscIOPin::Group1Io1.into(),
shield_ios: 0, // no shield
sampling_ios: TscIOPin::Group1Io2.into(),
};
let mut g1: PinGroup<embassy_stm32::peripherals::TSC, G1> = PinGroup::new();
g1.set_io1(context.PA0, PinType::Sample);
g1.set_io2(context.PA1, PinType::Channel);
let mut touch_controller = tsc::Tsc::new_async(
context.TSC,
Some(g1),
None,
None,
None,
None,
None,
None,
None,
config,
Irqs,
);
// Check if TSC is ready
if touch_controller.get_state() != State::Ready {
info!("TSC not ready!");
loop {} // Halt execution
}
info!("TSC initialized successfully");
// LED2 on the STM32L073RZ nucleo-board (PA5)
let mut led = Output::new(context.PA5, Level::High, Speed::Low);
// smaller sample capacitor discharge faster and can be used with shorter delay.
let discharge_delay = 5; // ms
info!("Starting touch_controller interface");
loop {
touch_controller.start();
touch_controller.pend_for_acquisition().await;
touch_controller.discharge_io(true);
Timer::after_millis(discharge_delay).await;
let grp1_status = touch_controller.group_get_status(Group::One);
match grp1_status {
GroupStatus::Complete => {
let group_one_val = touch_controller.group_get_value(Group::One);
info!("{}", group_one_val);
led.set_high();
}
GroupStatus::Ongoing => led.set_low(),
}
}
}

116
examples/stm32l0/src/bin/blocking-tsc.rs
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@@ -1,116 +0,0 @@
// Example of polling TSC (Touch Sensing Controller) that lights an LED when touch is detected.
//
// Suggested physical setup on STM32L073RZ Nucleo board:
// - Connect a 1000pF capacitor between pin A0 and GND. This is your sampling capacitor.
// - Connect one end of a 1K resistor to pin A1 and leave the other end loose.
// The loose end will act as touch sensor which will register your touch.
//
// Troubleshooting the setup:
// - If no touch seems to be registered, then try to disconnect the sampling capacitor from GND momentarily,
// now the led should light up. Next try using a different value for the sampling capacitor.
// Also experiment with increasing the values for `ct_pulse_high_length`, `ct_pulse_low_length`, `pulse_generator_prescaler`, `max_count_value` and `discharge_delay`.
//
// All configuration values and sampling capacitor value have been determined experimentally.
// Suitable configuration and discharge delay values are highly dependent on the value of the sample capacitor. For example, a shorter discharge delay can be used with smaller capacitor values.
//
#![no_std]
#![no_main]
use defmt::*;
use embassy_stm32::gpio::{Level, Output, Speed};
use embassy_stm32::tsc::{self, *};
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};
/// This example is written for the nucleo-stm32l073rz, with a stm32l073rz chip.
///
/// Make sure you check/update the following (whether you use the L073RZ or another board):
///
/// * [ ] Update .cargo/config.toml with the correct `probe-rs run --chip STM32L073RZTx`chip name.
/// * [ ] Update Cargo.toml to have the correct `embassy-stm32` feature, for L073RZ it should be `stm32l073rz`.
/// * [ ] If your board has a special clock or power configuration, make sure that it is
/// set up appropriately.
/// * [ ] If your board has different pin mapping, update any pin numbers or peripherals
/// to match your schematic
///
/// If you are unsure, please drop by the Embassy Matrix chat for support, and let us know:
///
/// * Which example you are trying to run
/// * Which chip and board you are using
///
/// Embassy Chat: https://matrix.to/#/#embassy-rs:matrix.org
#[embassy_executor::main]
async fn main(_spawner: embassy_executor::Spawner) {
let device_config = embassy_stm32::Config::default();
let context = embassy_stm32::init(device_config);
let tsc_conf = 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,
channel_ios: TscIOPin::Group1Io1.into(),
shield_ios: 0, // no shield
sampling_ios: TscIOPin::Group1Io2.into(),
};
let mut g1: PinGroup<embassy_stm32::peripherals::TSC, G1> = PinGroup::new();
g1.set_io1(context.PA0, PinType::Sample);
g1.set_io2(context.PA1, PinType::Channel);
let mut touch_controller = tsc::Tsc::new_blocking(
context.TSC,
Some(g1),
None,
None,
None,
None,
None,
None,
None,
tsc_conf,
);
// Check if TSC is ready
if touch_controller.get_state() != State::Ready {
info!("TSC not ready!");
loop {} // Halt execution
}
info!("TSC initialized successfully");
// LED2 on the STM32L073RZ nucleo-board (PA5)
let mut led = Output::new(context.PA5, Level::High, Speed::Low);
// smaller sample capacitor discharge faster and can be used with shorter delay.
let discharge_delay = 5; // ms
// the interval at which the loop polls for new touch sensor values
let polling_interval = 100; // ms
info!("polling for touch");
loop {
touch_controller.start();
touch_controller.poll_for_acquisition();
touch_controller.discharge_io(true);
Timer::after_millis(discharge_delay).await;
let grp1_status = touch_controller.group_get_status(Group::One);
match grp1_status {
GroupStatus::Complete => {
let group_one_val = touch_controller.group_get_value(Group::One);
info!("{}", group_one_val);
led.set_high();
}
GroupStatus::Ongoing => led.set_low(),
}
Timer::after_millis(polling_interval).await;
}
}

116
examples/stm32l0/src/bin/tsc_async.rs Normal file
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// Example of async TSC (Touch Sensing Controller) that lights an LED when touch is detected.
//
// This example demonstrates:
// 1. Configuring a single TSC channel pin
// 2. Using the blocking TSC interface with polling
// 3. Waiting for acquisition completion using `poll_for_acquisition`
// 4. Reading touch values and controlling an LED based on the results
//
// Suggested physical setup on STM32L073RZ Nucleo board:
// - Connect a 1000pF capacitor between pin PA0 and GND. This is your sampling capacitor.
// - Connect one end of a 1K resistor to pin PA1 and leave the other end loose.
// The loose end will act as the touch sensor which will register your touch.
//
// The example uses two pins from Group 1 of the TSC on the STM32L073RZ Nucleo board:
// - PA0 as the sampling capacitor, TSC group 1 IO1 (label A0)
// - PA1 as the channel pin, TSC group 1 IO2 (label A1)
//
// The program continuously reads the touch sensor value:
// - It starts acquisition, waits for completion using `poll_for_acquisition`, and reads the value.
// - The LED is turned on when touch is detected (sensor value < 25).
// - Touch values are logged to the console.
//
// Troubleshooting:
// - If touch is not detected, try adjusting the SENSOR_THRESHOLD value.
// - Experiment with different values for ct_pulse_high_length, ct_pulse_low_length,
// pulse_generator_prescaler, max_count_value, and discharge_delay to optimize sensitivity.
//
// Note: Configuration values and sampling capacitor value have been determined experimentally.
// Optimal values may vary based on your specific hardware setup.
// Pins have been chosen for their convenient locations on the STM32L073RZ board. Refer to the
// official relevant STM32 datasheets and nucleo-board user manuals to find suitable
// alternative pins.
//
// Beware for STM32L073RZ nucleo-board, that PA2 and PA3 is used for the uart connection to
// the programmer chip. If you try to use these two pins for TSC, you will get strange
// readings, unless you somehow reconfigure/re-wire your nucleo-board.
// No errors or warnings will be emitted, they will just silently not work as expected.
// (see nucleo user manual UM1724, Rev 14, page 25)
#![no_std]
#![no_main]
use defmt::*;
use embassy_stm32::gpio::{Level, Output, Speed};
use embassy_stm32::tsc::{self, *};
use embassy_stm32::{bind_interrupts, peripherals};
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};
bind_interrupts!(struct Irqs {
TSC => InterruptHandler<embassy_stm32::peripherals::TSC>;
});
const SENSOR_THRESHOLD: u16 = 25; // Adjust this value based on your setup
#[embassy_executor::main]
async fn main(_spawner: embassy_executor::Spawner) {
let device_config = embassy_stm32::Config::default();
let context = embassy_stm32::init(device_config);
let mut pin_group: PinGroupWithRoles<peripherals::TSC, G1> = PinGroupWithRoles::default();
pin_group.set_io1::<tsc_pin_roles::Sample>(context.PA0);
let sensor = pin_group.set_io2::<tsc_pin_roles::Channel>(context.PA1);
let tsc_conf = 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 pin_groups: PinGroups<peripherals::TSC> = PinGroups {
g1: Some(pin_group.pin_group),
..Default::default()
};
let mut touch_controller = tsc::Tsc::new_async(context.TSC, pin_groups, tsc_conf, Irqs).unwrap();
// Check if TSC is ready
if touch_controller.get_state() != State::Ready {
info!("TSC not ready!");
return;
}
info!("TSC initialized successfully");
// LED2 on the STM32L073RZ nucleo-board (PA5)
let mut led = Output::new(context.PA5, Level::Low, Speed::Low);
let discharge_delay = 5; // ms
info!("Starting touch_controller interface");
loop {
touch_controller.set_active_channels_mask(sensor.pin.into());
touch_controller.start();
touch_controller.pend_for_acquisition().await;
touch_controller.discharge_io(true);
Timer::after_millis(discharge_delay).await;
let group_val = touch_controller.group_get_value(sensor.pin.group());
info!("Touch value: {}", group_val);
if group_val < SENSOR_THRESHOLD {
led.set_high();
} else {
led.set_low();
}
Timer::after_millis(100).await;
}
}

142
examples/stm32l0/src/bin/tsc_blocking.rs Normal file
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// Example of blocking TSC (Touch Sensing Controller) that lights an LED when touch is detected.
//
// This example demonstrates:
// 1. Configuring a single TSC channel pin
// 2. Using the blocking TSC interface with polling
// 3. Waiting for acquisition completion using `poll_for_acquisition`
// 4. Reading touch values and controlling an LED based on the results
//
// Suggested physical setup on STM32L073RZ Nucleo board:
// - Connect a 1000pF capacitor between pin PA0 and GND. This is your sampling capacitor.
// - Connect one end of a 1K resistor to pin PA1 and leave the other end loose.
// The loose end will act as the touch sensor which will register your touch.
//
// The example uses two pins from Group 1 of the TSC on the STM32L073RZ Nucleo board:
// - PA0 as the sampling capacitor, TSC group 1 IO1 (label A0)
// - PA1 as the channel pin, TSC group 1 IO2 (label A1)
//
// The program continuously reads the touch sensor value:
// - It starts acquisition, waits for completion using `poll_for_acquisition`, and reads the value.
// - The LED is turned on when touch is detected (sensor value < 25).
// - Touch values are logged to the console.
//
// Troubleshooting:
// - If touch is not detected, try adjusting the SENSOR_THRESHOLD value.
// - Experiment with different values for ct_pulse_high_length, ct_pulse_low_length,
// pulse_generator_prescaler, max_count_value, and discharge_delay to optimize sensitivity.
//
// Note: Configuration values and sampling capacitor value have been determined experimentally.
// Optimal values may vary based on your specific hardware setup.
// Pins have been chosen for their convenient locations on the STM32L073RZ board. Refer to the
// official relevant STM32 datasheets and nucleo-board user manuals to find suitable
// alternative pins.
//
// Beware for STM32L073RZ nucleo-board, that PA2 and PA3 is used for the uart connection to
// the programmer chip. If you try to use these two pins for TSC, you will get strange
// readings, unless you somehow reconfigure/re-wire your nucleo-board.
// No errors or warnings will be emitted, they will just silently not work as expected.
// (see nucleo user manual UM1724, Rev 14, page 25)
#![no_std]
#![no_main]
use defmt::*;
use embassy_stm32::gpio::{Level, Output, Speed};
use embassy_stm32::tsc::{self, *};
use embassy_stm32::{mode, peripherals};
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};
const SENSOR_THRESHOLD: u16 = 25; // Adjust this value based on your setup
#[embassy_executor::main]
async fn main(_spawner: embassy_executor::Spawner) {
let device_config = embassy_stm32::Config::default();
let context = embassy_stm32::init(device_config);
let tsc_conf = 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 g1: PinGroupWithRoles<peripherals::TSC, G1> = PinGroupWithRoles::default();
g1.set_io1::<tsc_pin_roles::Sample>(context.PA0);
let tsc_sensor = g1.set_io2::<tsc_pin_roles::Channel>(context.PA1);
let pin_groups: PinGroups<peripherals::TSC> = PinGroups {
g1: Some(g1.pin_group),
..Default::default()
};
let mut touch_controller = tsc::Tsc::new_blocking(context.TSC, pin_groups, tsc_conf).unwrap();
// Check if TSC is ready
if touch_controller.get_state() != State::Ready {
crate::panic!("TSC not ready!");
}
info!("TSC initialized successfully");
// LED2 on the STM32L073RZ nucleo-board (PA5)
let mut led = Output::new(context.PA5, Level::High, Speed::Low);
// smaller sample capacitor discharge faster and can be used with shorter delay.
let discharge_delay = 5; // ms
// the interval at which the loop polls for new touch sensor values
let polling_interval = 100; // ms
info!("polling for touch");
loop {
touch_controller.set_active_channels_mask(tsc_sensor.pin.into());
touch_controller.start();
touch_controller.poll_for_acquisition();
touch_controller.discharge_io(true);
Timer::after_millis(discharge_delay).await;
match read_touch_value(&mut touch_controller, tsc_sensor.pin).await {
Some(v) => {
info!("sensor value {}", v);
if v < SENSOR_THRESHOLD {
led.set_high();
} else {
led.set_low();
}
}
None => led.set_low(),
}
Timer::after_millis(polling_interval).await;
}
}
const MAX_GROUP_STATUS_READ_ATTEMPTS: usize = 10;
// attempt to read group status and delay when still ongoing
async fn read_touch_value(
touch_controller: &mut tsc::Tsc<'_, peripherals::TSC, mode::Blocking>,
sensor_pin: TscIOPin,
) -> Option<u16> {
for _ in 0..MAX_GROUP_STATUS_READ_ATTEMPTS {
match touch_controller.group_get_status(sensor_pin.group()) {
GroupStatus::Complete => {
return Some(touch_controller.group_get_value(sensor_pin.group()));
}
GroupStatus::Ongoing => {
// if you end up here a lot, then you prob need to increase discharge_delay
// or consider changing the code to adjust the discharge_delay dynamically
info!("Acquisition still ongoing");
Timer::after_millis(1).await;
}
}
}
None
}

233
examples/stm32l0/src/bin/tsc_multipin.rs Normal file
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// Example of TSC (Touch Sensing Controller) using multiple pins from the same tsc-group.
//
// What is special about using multiple TSC pins as sensor channels from the same TSC group,
// is that only one TSC pin for each TSC group can be acquired and read at the time.
// To control which channel pins are acquired and read, we must write a mask before initiating an
// acquisition. To help manage and abstract all this business away, we can organize our channel
// pins into acquisition banks. Each acquisition bank can contain exactly one channel pin per TSC
// group and it will contain the relevant mask.
//
// This example demonstrates how to:
// 1. Configure multiple channel pins within a single TSC group
// 2. Use the set_active_channels method to switch between different channels
// 3. Read and interpret touch values from multiple channels in the same group
//
// Suggested physical setup on STM32L073RZ Nucleo board:
// - Connect a 1000pF capacitor between pin PA0 (label A0) and GND. This is the sampling capacitor for TSC
// group 1.
// - Connect one end of a 1K resistor to pin PA1 (label A1) and leave the other end loose.
// The loose end will act as a touch sensor.
//
// - Connect a 1000pF capacitor between pin PB3 (label D3) and GND. This is the sampling capacitor for TSC
// group 5.
// - Connect one end of another 1K resistor to pin PB4 and leave the other end loose.
// The loose end will act as a touch sensor.
// - Connect one end of another 1K resistor to pin PB6 and leave the other end loose.
// The loose end will act as a touch sensor.
//
// The example uses pins from two TSC groups.
// - PA0 as sampling capacitor, TSC group 1 IO1 (label A0)
// - PA1 as channel, TSC group 1 IO2 (label A1)
// - PB3 as sampling capacitor, TSC group 5 IO1 (label D3)
// - PB4 as channel, TSC group 5 IO2 (label D3)
// - PB6 as channel, TSC group 5 IO3 (label D5)
//
// The pins have been chosen to make it easy to simply add capacitors directly onto the board and
// connect one leg to GND, and to easily add resistors to the board with no special connectors,
// breadboards, special wires or soldering required. All you need is the capacitors and resistors.
//
// The program reads the designated channel pins and adjusts the LED blinking
// pattern based on which sensor(s) are touched:
// - No touch: LED off
// - one sensor touched: Slow blinking
// - two sensors touched: Fast blinking
// - three sensors touched: LED constantly on
//
// Troubleshooting:
// - If touch is not detected, try adjusting the SENSOR_THRESHOLD value.
// - Experiment with different values for ct_pulse_high_length, ct_pulse_low_length,
// pulse_generator_prescaler, max_count_value, and discharge_delay to optimize sensitivity.
//
// Note: Configuration values and sampling capacitor value have been determined experimentally.
// Optimal values may vary based on your specific hardware setup.
// Pins have been chosen for their convenient locations on the STM32L073RZ board. Refer to the
// official relevant STM32 datasheets and nucleo-board user manuals to find suitable
// alternative pins.
//
// Beware for STM32L073RZ nucleo-board, that PA2 and PA3 is used for the uart connection to
// the programmer chip. If you try to use these two pins for TSC, you will get strange
// readings, unless you somehow reconfigure/re-wire your nucleo-board.
// No errors or warnings will be emitted, they will just silently not work as expected.
// (see nucleo user manual UM1724, Rev 14, page 25)
#![no_std]
#![no_main]
use defmt::*;
use embassy_stm32::gpio::{Level, Output, Speed};
use embassy_stm32::tsc::{self, *};
use embassy_stm32::{bind_interrupts, mode, peripherals};
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};
bind_interrupts!(struct Irqs {
TSC => InterruptHandler<embassy_stm32::peripherals::TSC>;
});
const MAX_GROUP_STATUS_READ_ATTEMPTS: usize = 10;
async fn read_touch_values(
touch_controller: &mut tsc::Tsc<'_, peripherals::TSC, mode::Async>,
tsc_acquisition_bank: &TscAcquisitionBank,
) -> Option<TscAcquisitionBankReadings> {
for _ in 0..MAX_GROUP_STATUS_READ_ATTEMPTS {
let status = touch_controller.get_acquisition_bank_status(tsc_acquisition_bank);
if status.all_complete() {
let r = touch_controller.get_acquisition_bank_values(tsc_acquisition_bank);
return Some(r);
} else {
info!("Acquisition still ongoing");
Timer::after_millis(1).await;
}
}
info!("Acquisition failed after {} attempts", MAX_GROUP_STATUS_READ_ATTEMPTS);
None
}
const SENSOR_THRESHOLD: u16 = 35;
async fn acquire_sensors(
touch_controller: &mut Tsc<'static, peripherals::TSC, mode::Async>,
tsc_acquisition_bank: &TscAcquisitionBank,
) {
touch_controller.set_active_channels_mask(tsc_acquisition_bank.mask());
touch_controller.start();
touch_controller.pend_for_acquisition().await;
touch_controller.discharge_io(true);
let discharge_delay = 5; // ms
Timer::after_millis(discharge_delay).await;
}
#[embassy_executor::main]
async fn main(_spawner: embassy_executor::Spawner) {
let device_config = embassy_stm32::Config::default();
let context = embassy_stm32::init(device_config);
// ---------- initial configuration of TSC ----------
let mut pin_group1: PinGroupWithRoles<peripherals::TSC, G1> = PinGroupWithRoles::default();
pin_group1.set_io1::<tsc_pin_roles::Sample>(context.PA0);
let tsc_sensor0 = pin_group1.set_io2(context.PA1);
let mut pin_group5: PinGroupWithRoles<peripherals::TSC, G5> = PinGroupWithRoles::default();
pin_group5.set_io1::<tsc_pin_roles::Sample>(context.PB3);
let tsc_sensor1 = pin_group5.set_io2(context.PB4);
let tsc_sensor2 = pin_group5.set_io3(context.PB6);
let config = tsc::Config {
ct_pulse_high_length: ChargeTransferPulseCycle::_16,
ct_pulse_low_length: ChargeTransferPulseCycle::_16,
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 pin_groups: PinGroups<peripherals::TSC> = PinGroups {
g1: Some(pin_group1.pin_group),
g5: Some(pin_group5.pin_group),
..Default::default()
};
let mut touch_controller = tsc::Tsc::new_async(context.TSC, pin_groups, config, Irqs).unwrap();
// ---------- setting up acquisition banks ----------
// sensor0 and sensor1 in this example belong to different TSC-groups,
// therefore we can acquire and read them both in one go.
let bank1 = touch_controller.create_acquisition_bank(TscAcquisitionBankPins {
g1_pin: Some(tsc_sensor0),
g5_pin: Some(tsc_sensor1),
..Default::default()
});
// `sensor1` and `sensor2` belongs to the same TSC-group, therefore we must make sure to
// acquire them one at the time. Therefore, we organize them into different acquisition banks.
let bank2 = touch_controller.create_acquisition_bank(TscAcquisitionBankPins {
g5_pin: Some(tsc_sensor2),
..Default::default()
});
// Check if TSC is ready
if touch_controller.get_state() != State::Ready {
crate::panic!("TSC not ready!");
}
info!("TSC initialized successfully");
// LED2 on the STM32L073RZ nucleo-board (PA5)
let mut led = Output::new(context.PA5, Level::High, Speed::Low);
let mut led_state = false;
loop {
acquire_sensors(&mut touch_controller, &bank1).await;
let readings1: TscAcquisitionBankReadings = read_touch_values(&mut touch_controller, &bank1)
.await
.expect("should be able to read values for bank 1");
acquire_sensors(&mut touch_controller, &bank2).await;
let readings2: TscAcquisitionBankReadings = read_touch_values(&mut touch_controller, &bank2)
.await
.expect("should be able to read values for bank 2");
let mut touched_sensors_count = 0;
for reading in readings1.iter() {
info!("{}", reading);
if reading.sensor_value < SENSOR_THRESHOLD {
touched_sensors_count += 1;
}
}
for reading in readings2.iter() {
info!("{}", reading);
if reading.sensor_value < SENSOR_THRESHOLD {
touched_sensors_count += 1;
}
}
match touched_sensors_count {
0 => {
// No sensors touched, turn off the LED
led.set_low();
led_state = false;
}
1 => {
// One sensor touched, blink slowly
led_state = !led_state;
if led_state {
led.set_high();
} else {
led.set_low();
}
Timer::after_millis(200).await;
}
2 => {
// Two sensors touched, blink faster
led_state = !led_state;
if led_state {
led.set_high();
} else {
led.set_low();
}
Timer::after_millis(50).await;
}
3 => {
// All three sensors touched, LED constantly on
led.set_high();
led_state = true;
}
_ => crate::unreachable!(), // This case should never occur with 3 sensors
}
}
}