Add 0x09_dht11_rust: DHT11 temperature/humidity sensor driver

drivers/0x09_dht11_rust/src/main.rs

@@ -0,0 +1,120 @@
+//! @file main.rs
+//! @brief DHT11 temperature and humidity sensor demonstration
+//! @author Kevin Thomas
+//! @date 2025
+//!
+//! MIT License
+//!
+//! Copyright (c) 2025 Kevin Thomas
+//!
+//! Permission is hereby granted, free of charge, to any person obtaining a copy
+//! of this software and associated documentation files (the "Software"), to deal
+//! in the Software without restriction, including without limitation the rights
+//! to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//! copies of the Software, and to permit persons to whom the Software is
+//! furnished to do so, subject to the following conditions:
+//!
+//! The above copyright notice and this permission notice shall be included in
+//! all copies or substantial portions of the Software.
+//!
+//! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//! IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//! FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//! AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//! LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//! OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//! SOFTWARE.
+//!
+//! -----------------------------------------------------------------------------
+//!
+//! Demonstrates how to read temperature and humidity from a DHT11
+//! sensor using the dht11.rs driver. The sensor is polled every 2
+//! seconds (the minimum safe interval for the DHT11) and the results
+//! are printed over UART. A failed read is reported so wiring issues
+//! are visible.
+//!
+//! Wiring:
+//!   GPIO4 -> DHT11 DATA pin  (10 kohm pull-up to 3.3 V recommended)
+//!   3.3V  -> DHT11 VCC
+//!   GND   -> DHT11 GND
+
+#![no_std]
+#![no_main]
+
+// Board-level helpers: constants, type aliases, and init functions
+mod board;
+// DHT11 driver module — suppress warnings for unused public API functions
+#[allow(dead_code)]
+mod dht11;
+
+// Debugging output over RTT
+use defmt_rtt as _;
+// Panic handler for RISC-V targets
+#[cfg(target_arch = "riscv32")]
+use panic_halt as _;
+// Panic handler for ARM targets
+#[cfg(target_arch = "arm")]
+use panic_probe as _;
+
+// HAL entry-point macro
+use hal::entry;
+
+// Alias our HAL crate
+#[cfg(rp2350)]
+use rp235x_hal as hal;
+#[cfg(rp2040)]
+use rp2040_hal as hal;
+
+// Second-stage boot loader for RP2040
+#[unsafe(link_section = ".boot2")]
+#[used]
+#[cfg(rp2040)]
+pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
+
+// Boot metadata for the RP2350 Boot ROM
+#[unsafe(link_section = ".start_block")]
+#[used]
+#[cfg(rp2350)]
+pub static IMAGE_DEF: hal::block::ImageDef = hal::block::ImageDef::secure_exe();
+
+/// Application entry point for the DHT11 sensor demo.
+///
+/// Initializes the DHT11 on GPIO4 and continuously reads temperature
+/// and humidity, printing results over UART every 2 seconds.
+///
+/// # Returns
+///
+/// Does not return.
+#[entry]
+fn main() -> ! {
+    let mut pac = hal::pac::Peripherals::take().unwrap();
+    let clocks = board::init_clocks(
+        pac.XOSC, pac.CLOCKS, pac.PLL_SYS, pac.PLL_USB, &mut pac.RESETS,
+        &mut hal::Watchdog::new(pac.WATCHDOG),
+    );
+    let pins = board::init_pins(pac.IO_BANK0, pac.PADS_BANK0, pac.SIO, &mut pac.RESETS);
+    let uart = board::init_uart(pac.UART0, pins.gpio0, pins.gpio1, &mut pac.RESETS, &clocks);
+    let mut delay = board::init_delay(&clocks);
+    #[cfg(rp2350)]
+    let timer = hal::Timer::new_timer0(pac.TIMER0, &mut pac.RESETS, &clocks);
+    #[cfg(rp2040)]
+    let timer = hal::Timer::new(pac.TIMER, &mut pac.RESETS);
+    let _dht_pin = pins.gpio4.into_pull_up_input();
+    uart.write_full_blocking(b"DHT11 driver initialized on GPIO 4\r\n");
+    loop {
+        board::poll_sensor(&uart, &timer, &mut delay);
+    }
+}
+
+// Picotool binary info metadata
+#[unsafe(link_section = ".bi_entries")]
+#[used]
+pub static PICOTOOL_ENTRIES: [hal::binary_info::EntryAddr; 5] = [
+    hal::binary_info::rp_cargo_bin_name!(),
+    hal::binary_info::rp_cargo_version!(),
+    hal::binary_info::rp_program_description!(c"DHT11 Sensor Demo"),
+    hal::binary_info::rp_cargo_homepage_url!(),
+    hal::binary_info::rp_program_build_attribute!(),
+];
+
+// End of file