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Hints

STOP!

If you ended up here by mistake, do not proceed forward. SPOILERS AHEAD!

Hi, I am new here! - Hint 01​

Try using the info! macro. It's syntax is identical to the one used by print! and println!, found in the standard library.

Hi, I am new here! - Hint 02​

The wait_for_* functions are particularly interesting. Try to figure out which one should you use.

Hi, I am new here! - Hint 03​

I know you can do it, give yourself a bit of a challenge.

Sing your own tune - Hint 01​

You will need to use the table in Section 12.5.2. Programmer's Model to figure out the PWM channel for the chosen pin. The function you will need to use the pwm::Config, to modify the top and compare registers' values and the Pwm::new_output_X() function, where X will be either a or b, depending on the pin's channel. The first argument will have to be the PWM slice of the pin, the second one the pin itself, and the third, the PWM config. To be able to reuse the config later, you can pass a clone to the function.

Sing your own tune - Hint 02​

/// Beats per minute.
const TEMPO: u64 = 100;
/// A whole note duration in milliseconds.
const WHOLE_NOTE: u64 = 4 * (60_000 / TEMPO)
/// The microcontroller clock frequency
const CLOCK_FREQ: u64 = 150_000_000;
/// PWM clock divider
const PWM_DIV: u64 = 64;

Sing your own tune - Hint 03​

note_freq = cpu_freq / (divider * top)

In order to configure the PWM output, you can use the default value, and change the divider filed of the pwm::Config. The code should look like this:

let buzzer_cfg = pwm::Config::default();
buzzer_cfg.divider = PWM_DIV.to_fixed();
let mut buzzer = pwm::Pwm::new_output_x(
    p.PWM_SLICEX,
    p.PIN_Y,
    buzzer_cfg.clone()
);

Where the Y is the pin number, and the slice number (X) and half (x) depend on the choice of pin.

For each note, you will need to change the PWM configuration. Take a look at the methods implemented for the Pwm structure.

The temperature is rising - Hint 01​

RGB colors are represented as 3 bytes, one for each color channel. Red is (255, 0, 0) and blue is (0, 0, 255). You will need to configure 3 PWM output pins, one for each of the three colors and wire them accordingly. For simplicity, you should set the top register to be 255, and because the LED is a common anode, the control is reversed. So if I would like to produce a color that has 180 in the red channel, I need to set the compare register value to 75(255 - 180).

To make the light fade from red to blue, you can simply interpolate between the two points at a regular interval (such as 10ms, for example), with a given step.

The temperature is rising - Hint 02​

This is how you can bind the I2C interrupt:

embassy_rp::bind_interrupts!(struct Irqs {
    // Do not forget to bind the I2C peripheral interrupt to its handler
    I2CX_IRQ => embassy_rp::i2c::InterruptHandler<embassy_rp::peripherals::I2CX>;
});

where X is the peripheral number, that should correspond with the two pins you chose to use.

The bus declaration should look like this:

let bus = I2c::new_async(p.I2C1, p.PIN_7, p.PIN_6, Irqs, Default::default());

and to instantiate the BMP280 structure, use the new() function and pass the bus we just created. Do not forget to configure the oversampling rates and power mode, using the set_control() function. Then, simply read the temperature.