diff --git a/Cargo.lock b/Cargo.lock
index eb9e760..85855fa 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,49 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "bitflags"
+version = "2.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "812e12b5285cc515a9c72a5c1d3b6d46a19dac5acfef5265968c166106e31dd3"
+
+[[package]]
+name = "cfg-if"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
+
+[[package]]
+name = "gpio-cdev"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09831ec59b80be69e75d29cf36e16afbbe5fd1af9c1bf4689ad91c77db5aa6a6"
+dependencies = [
+ "bitflags",
+ "libc",
+ "nix",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.178"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37c93d8daa9d8a012fd8ab92f088405fb202ea0b6ab73ee2482ae66af4f42091"
+
+[[package]]
+name = "nix"
+version = "0.27.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2eb04e9c688eff1c89d72b407f168cf79bb9e867a9d3323ed6c01519eb9cc053"
+dependencies = [
+ "bitflags",
+ "cfg-if",
+ "libc",
+]
+
 [[package]]
 name = "snooze-pal"
 version = "0.1.0"
+dependencies = [
+ "gpio-cdev",
+]
diff --git a/Cargo.toml b/Cargo.toml
index 76b7d75..5642777 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,3 +4,4 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+gpio-cdev = "0.6.0"
diff --git a/src/main.rs b/src/main.rs
index ec1fd02..1c7319b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,6 +1,34 @@
 // This project is licensed under MIT Licese.
 // See the LICENSE folder for details.
 
-fn main() {
-    println!("Hello, world!!");
+use std::thread;
+
+use gpio_cdev::{Chip, LineRequestFlags};
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut chip = Chip::new("/dev/gpiochip0")?;
+    alarm(&mut chip)?;
+    Ok(())
+}
+
+fn alarm(chip: &mut Chip) -> Result<(), Box<dyn std::error::Error>> {
+    let beeper = chip
+        .get_line(17)?
+        .request(LineRequestFlags::OUTPUT, 0, "my-gpio")?;
+
+    for _ in 0..5 {
+        beeper.set_value(1)?;
+        thread::sleep(std::time::Duration::from_secs(1));
+        beeper.set_value(0)?;
+        thread::sleep(std::time::Duration::from_secs(1));
+    }
+
+    Ok(())
+}
+
+fn turn_off_led(chip: &mut Chip) -> Result<(), Box<dyn std::error::Error>> {
+    chip.get_line(17)?
+        .request(LineRequestFlags::OUTPUT, 0, "my-gpio")?
+        .set_value(0)?;
+    Ok(())
 }