embassy_rp: implement pwm traits from embedded_hal

• Update crate versions • Implement embedded-hal PWM traits • Add TB6612FNG motor driver example

2 files changed, 117 insertions, 0 deletions

diff --git a/examples/rp23/Cargo.toml b/examples/rp23/Cargo.toml
index 08646463c..f35e3a11d 100644
--- a/examples/rp23/Cargo.toml
+++ b/examples/rp23/Cargo.toml
@@ -30,6 +30,9 @@ serde-json-core = "0.5.1"
 # for assign resources example
 assign-resources = { git = "https://github.com/adamgreig/assign-resources", rev = "94ad10e2729afdf0fd5a77cd12e68409a982f58a" }
 
+# for TB6612FNG example
+tb6612fng = "1.0.0"
+
 #cortex-m = { version = "0.7.6", features = ["critical-section-single-core"] }
 cortex-m = { version = "0.7.6", features = ["inline-asm"] }
 cortex-m-rt = "0.7.0"
diff --git a/examples/rp23/src/bin/pwm_tb6612fng_motor_driver.rs b/examples/rp23/src/bin/pwm_tb6612fng_motor_driver.rs
new file mode 100644
index 000000000..92c1ff6ba
--- /dev/null
+++ b/examples/rp23/src/bin/pwm_tb6612fng_motor_driver.rs
@@ -0,0 +1,114 @@
+//! # PWM TB6612FNG motor driver
+//! 
+//! This example shows the use of a TB6612FNG motor driver. The driver is built on top of embedded_hal and the example demonstrates how embassy_rp can be used to interact with ist.
+
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_rp::block::ImageDef;
+use embassy_rp::config::Config;
+use embassy_rp::gpio::Output;
+use embassy_rp::peripherals;
+use embassy_rp::gpio;
+use embassy_rp::pwm;
+use embassy_time::Duration;
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+use tb6612fng::{DriveCommand, Motor, Tb6612fng};
+use assign_resources::assign_resources;
+
+/// Maximum PWM value (fully on)
+const PWM_MAX: u16 = 50000;
+
+/// Minimum PWM value (fully off)
+const PWM_MIN: u16 = 0;
+
+#[link_section = ".start_block"]
+#[used]
+pub static IMAGE_DEF: ImageDef = ImageDef::secure_exe();
+
+assign_resources! {
+    motor: MotorResources {
+        standby_pin: PIN_22,
+        left_slice: PWM_SLICE6,
+        left_pwm_pin: PIN_28,
+        left_forward_pin: PIN_21,
+        left_backward_pin: PIN_20,
+        right_slice: PWM_SLICE5,
+        right_pwm_pin: PIN_27,
+        right_forward_pin: PIN_19,
+        right_backward_pin: PIN_18,
+        },
+}
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Config::default());
+    let s = split_resources!(p);
+    let r = s.motor;
+
+    // we need a standby output and two motors to construct a full TB6612FNG
+
+    // standby pin
+    let stby = Output::new(r.standby_pin, gpio::Level::Low);
+
+    // motor A, here defined to be the left motor
+    let left_fwd = gpio::Output::new(r.left_forward_pin, gpio::Level::Low);
+    let left_bckw = gpio::Output::new(r.left_backward_pin, gpio::Level::Low);
+    let mut left_speed = pwm::Config::default();
+    left_speed.top = PWM_MAX;
+    left_speed.compare_a = PWM_MIN;
+    let left_pwm = pwm::Pwm::new_output_a(r.left_slice, r.left_pwm_pin, left_speed);
+    let left_motor = Motor::new(left_fwd, left_bckw, left_pwm).unwrap();
+
+    // motor B, here defined to be the right motor
+    let right_fwd = gpio::Output::new(r.right_forward_pin, gpio::Level::Low);
+    let right_bckw = gpio::Output::new(r.right_backward_pin, gpio::Level::Low);
+    let mut right_speed = pwm::Config::default();
+    right_speed.top = PWM_MAX;
+    right_speed.compare_b = PWM_MIN;
+    let right_pwm = pwm::Pwm::new_output_b(r.right_slice, r.right_pwm_pin, right_speed);
+    let right_motor = Motor::new(right_fwd, right_bckw, right_pwm).unwrap();
+
+    // construct the motor driver
+    let mut control = Tb6612fng::new(left_motor, right_motor, stby).unwrap();
+
+    loop {
+        // wake up the motor driver
+        info!("end standby");
+        control.disable_standby().unwrap();
+        Timer::after(Duration::from_millis(100)).await;
+
+        // drive a straight line forward at 20% speed for 5s
+        info!("drive straight");
+        control.motor_a.drive(DriveCommand::Forward(20)).unwrap();
+        control.motor_b.drive(DriveCommand::Forward(20)).unwrap();
+        Timer::after(Duration::from_secs(5)).await;
+
+        // coast for 2s
+        info!("coast");
+        control.motor_a.drive(DriveCommand::Stop).unwrap();
+        control.motor_b.drive(DriveCommand::Stop).unwrap();
+        Timer::after(Duration::from_secs(2)).await;
+
+        // actively brake
+        info!("brake"); 
+        control.motor_a.drive(DriveCommand::Brake).unwrap();
+        control.motor_b.drive(DriveCommand::Brake).unwrap();
+        Timer::after(Duration::from_secs(1)).await;
+
+        // slowly turn for 3s
+        info!( "turn");
+        control.motor_a.drive(DriveCommand::Backward(10)).unwrap();
+        control.motor_b.drive(DriveCommand::Forward(10)).unwrap();
+        Timer::after(Duration::from_secs(3)).await;
+
+        // and put the driver in standby mode and wait for 5s
+        info!( "standby");
+        control.enable_standby().unwrap();
+        Timer::after(Duration::from_secs(5)).await;
+    }
+}
+