mirror of
https://github.com/italicsjenga/rp-hal-boards.git
synced 2024-12-24 05:01:31 +11:00
f8984a9eac
Implementing `impl From<SystemClock> for Hertz` is a footgun, as
SystemClock is not Copy, so the automatic conversion consumes the
owned clock.
This is visible in the example i2c.rs:
```
let mut i2c = hal::I2C::i2c1(
pac.I2C1,
sda_pin,
scl_pin, // Try `not_an_scl_pin` here
400.kHz(),
&mut pac.RESETS,
clocks.peripheral_clock,
);
```
If the user wants to use both `i2c0` and `i2c1` at the same time,
copying from this example won't work:
```
error[E0382]: use of moved value: `clocks.peripheral_clock`
--> rp2040-hal/examples/i2c.rs:106:9
|
97 | clocks.peripheral_clock,
| ----------------------- value moved here
...
106 | clocks.peripheral_clock,
| ^^^^^^^^^^^^^^^^^^^^^^^ value used here after move
|
= note: move occurs because `clocks.peripheral_clock` has type
`PeripheralClock`, which does not implement the `Copy` trait
```
As getting the frequency from a clock doesn't really need ownership,
changing it to `impl From<&SystemClock> for Hertz` is both more
logical and provides better usability.
This is, however, a breaking change: Code relying on this trait
implementation needs to be changed by adding a `&`.
127 lines
3.8 KiB
Rust
127 lines
3.8 KiB
Rust
//! # ADC Example
|
|
//!
|
|
//! This application demonstrates how to read ADC samples from the temperature
|
|
//! sensor and pin and output them to the UART on pins 1 and 2 at 9600 baud.
|
|
//!
|
|
//! It may need to be adapted to your particular board layout and/or pin assignment.
|
|
//!
|
|
//! See the `Cargo.toml` file for Copyright and license details.
|
|
|
|
#![no_std]
|
|
#![no_main]
|
|
|
|
// The macro for our start-up function
|
|
use cortex_m_rt::entry;
|
|
|
|
// Ensure we halt the program on panic (if we don't mention this crate it won't
|
|
// be linked)
|
|
use panic_halt as _;
|
|
|
|
// Alias for our HAL crate
|
|
use rp2040_hal as hal;
|
|
|
|
// Some traits we need
|
|
use core::fmt::Write;
|
|
use embedded_hal::adc::OneShot;
|
|
use embedded_time::fixed_point::FixedPoint;
|
|
use rp2040_hal::Clock;
|
|
|
|
// A shorter alias for the Peripheral Access Crate, which provides low-level
|
|
// register access
|
|
use hal::pac;
|
|
|
|
/// The linker will place this boot block at the start of our program image. We
|
|
/// need this to help the ROM bootloader get our code up and running.
|
|
#[link_section = ".boot2"]
|
|
#[used]
|
|
pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
|
|
|
|
/// External high-speed crystal on the Raspberry Pi Pico board is 12 MHz. Adjust
|
|
/// if your board has a different frequency
|
|
const XTAL_FREQ_HZ: u32 = 12_000_000u32;
|
|
|
|
/// Entry point to our bare-metal application.
|
|
///
|
|
/// The `#[entry]` macro ensures the Cortex-M start-up code calls this function
|
|
/// as soon as all global variables are initialised.
|
|
///
|
|
/// The function configures the RP2040 peripherals, then prints the temperature
|
|
/// in an infinite loop.
|
|
#[entry]
|
|
fn main() -> ! {
|
|
// Grab our singleton objects
|
|
let mut pac = pac::Peripherals::take().unwrap();
|
|
let core = pac::CorePeripherals::take().unwrap();
|
|
|
|
// Set up the watchdog driver - needed by the clock setup code
|
|
let mut watchdog = hal::Watchdog::new(pac.WATCHDOG);
|
|
|
|
// Configure the clocks
|
|
let clocks = hal::clocks::init_clocks_and_plls(
|
|
XTAL_FREQ_HZ,
|
|
pac.XOSC,
|
|
pac.CLOCKS,
|
|
pac.PLL_SYS,
|
|
pac.PLL_USB,
|
|
&mut pac.RESETS,
|
|
&mut watchdog,
|
|
)
|
|
.ok()
|
|
.unwrap();
|
|
|
|
// The delay object lets us wait for specified amounts of time (in
|
|
// milliseconds)
|
|
let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer());
|
|
|
|
// The single-cycle I/O block controls our GPIO pins
|
|
let sio = hal::Sio::new(pac.SIO);
|
|
|
|
// Set the pins to their default state
|
|
let pins = hal::gpio::Pins::new(
|
|
pac.IO_BANK0,
|
|
pac.PADS_BANK0,
|
|
sio.gpio_bank0,
|
|
&mut pac.RESETS,
|
|
);
|
|
|
|
// UART TX (characters sent from pico) on pin 1 (GPIO0) and RX (on pin 2 (GPIO1)
|
|
let uart_pins = (
|
|
pins.gpio0.into_mode::<hal::gpio::FunctionUart>(),
|
|
pins.gpio1.into_mode::<hal::gpio::FunctionUart>(),
|
|
);
|
|
|
|
// Create a UART driver
|
|
let mut uart = hal::uart::UartPeripheral::new(pac.UART0, uart_pins, &mut pac.RESETS)
|
|
.enable(
|
|
hal::uart::common_configs::_9600_8_N_1,
|
|
clocks.peripheral_clock.freq(),
|
|
)
|
|
.unwrap();
|
|
|
|
// Write to the UART
|
|
uart.write_full_blocking(b"ADC example\r\n");
|
|
|
|
// Enable ADC
|
|
let mut adc = hal::Adc::new(pac.ADC, &mut pac.RESETS);
|
|
|
|
// Enable the temperature sense channel
|
|
let mut temperature_sensor = adc.enable_temp_sensor();
|
|
|
|
// Configure GPIO26 as an ADC input
|
|
let mut adc_pin_0 = pins.gpio26.into_floating_input();
|
|
loop {
|
|
// Read the raw ADC counts from the temperature sensor channel.
|
|
let temp_sens_adc_counts: u16 = adc.read(&mut temperature_sensor).unwrap();
|
|
let pin_adc_counts: u16 = adc.read(&mut adc_pin_0).unwrap();
|
|
writeln!(
|
|
uart,
|
|
"ADC readings: Temperature: {:02} Pin: {:02}\r\n",
|
|
temp_sens_adc_counts, pin_adc_counts
|
|
)
|
|
.unwrap();
|
|
delay.delay_ms(1000);
|
|
}
|
|
}
|
|
|
|
// End of file
|