diff --git a/Cargo.toml b/Cargo.toml
index ac29427..c5179f9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,8 +17,10 @@ pio = ["esp-idf-sys/pio"]
 
 [dependencies]
 anyhow = "1"
+embedded-hal = "0.2.7"
 embedded-svc = "0.22.0"
 env_logger = "0.9.0"
+esp-idf-hal = "0.38.0"
 esp-idf-svc = "0.42.1"
 esp-idf-sys = { version = "0.31.6", features = ["binstart"] }
 log = "0.4.17"
diff --git a/src/blink.rs b/src/blink.rs
new file mode 100644
index 0000000..e54e65e
--- /dev/null
+++ b/src/blink.rs
@@ -0,0 +1,47 @@
+use embedded_hal::digital::v2::OutputPin;
+use std::thread;
+use std::time::Duration;
+
+pub struct Blink<T>
+where
+    T: OutputPin,
+{
+    state: bool,
+    pin: T,
+    stopped: bool,
+}
+
+impl<T> Blink<T>
+where
+    T: OutputPin,
+{
+    pub fn new(pin: T) -> Blink<T> {
+        return Blink {
+            state: false,
+            pin,
+            stopped: false,
+        };
+    }
+
+    pub fn toggle(&mut self) -> Result<(), T::Error> {
+        self.state = !self.state;
+        if self.state {
+            self.pin.set_high()
+        } else {
+            self.pin.set_low()
+        }
+    }
+
+    pub fn play(&mut self) where <T as embedded_hal::digital::v2::OutputPin>::Error: std::fmt::Debug {
+        loop {
+            if self.stopped {
+                break;
+            }
+            self.toggle().unwrap();
+            thread::sleep(Duration::from_millis(30));
+
+            self.toggle().unwrap();
+            thread::sleep(Duration::from_millis(1930));
+        }
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 2cc21d0..126e62a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,13 +1,22 @@
-use std::{env, thread::sleep, time::{Duration}};
 use embedded_svc::mqtt::client::{Publish, QoS};
 use esp_idf_sys as _;
 use log::*;
+use std::{
+    env,
+    thread::{self, sleep},
+    time::Duration,
+};
 
+mod blink;
 mod message_queue;
-mod wifi;
 mod time;
+mod wifi;
+mod voltage_detection;
+
+use crate::{
+    message_queue::MessageQueue, time::Time, wifi::Internet, voltage_detection::VoltageDetection,
+};
 
-use crate::{message_queue::MessageQueue, wifi::Internet, time::Time};
 fn main() {
     env::set_var("DEFMT_LOG", "trace");
     env::set_var("RUST_BACKTRACE", "1");
@@ -18,7 +27,31 @@ fn main() {
     // or else some patches to the runtime implemented by esp-idf-sys might not link properly.
     esp_idf_sys::link_patches();
 
-    println!("Hello, world!");
+    info!("Hello, world!");
+
+    let peripherals = esp_idf_hal::peripherals::Peripherals::take().unwrap();
+
+    let blink_pin = peripherals.pins.gpio5;
+    let beep_pin = peripherals.pins.gpio6;
+    let ledc_timer0 = peripherals.ledc.timer0;
+    let ledc_channel0 = peripherals.ledc.channel0;
+    let dc_out_ctl_pin = peripherals.pins.gpio3;
+    let i2c0 = peripherals.i2c0;
+    let sda_pin = peripherals.pins.gpio4;
+    let scl_pin = peripherals.pins.gpio10;
+
+    thread::spawn(move || {
+        let mut blink = blink::Blink::new(
+            blink_pin
+                .into_output()
+                .expect("Failed to set GPIO5 as output"),
+        );
+        blink.play();
+    });
+
+    let mut voltage_detection = VoltageDetection::new();
+
+    voltage_detection.watching().expect("Can not watch voltages.");
 
     let _wifi = Internet::new().unwrap();
 
@@ -34,14 +67,15 @@ fn main() {
             let timestamps = time.get_time().as_millis();
 
             info!("timestamps {}", timestamps);
-            mq_client.publish(
-                "ups-0.2/heartbeat",
-                QoS::AtMostOnce,
-                false,
-                timestamps.to_string().as_bytes(),
-            ).map_err(|err| {
-                warn!("publish heartbeat failed {}", err)
-            }).unwrap();
+            mq_client
+                .publish(
+                    "ups-0.2/heartbeat",
+                    QoS::AtMostOnce,
+                    false,
+                    timestamps.to_string().as_bytes(),
+                )
+                .map_err(|err| warn!("publish heartbeat failed {}", err))
+                .unwrap();
         }
     }
 }
diff --git a/src/message_queue.rs b/src/message_queue.rs
index a899827..59b4056 100644
--- a/src/message_queue.rs
+++ b/src/message_queue.rs
@@ -24,7 +24,7 @@ impl MessageQueue {
         };
 
         let (mut client, mut connection) =
-            EspMqttClient::new_with_conn("mqtt://192.168.31.8:1883", &conf)?;
+            EspMqttClient::new_with_conn("mqtt://192.168.31.11:1883", &conf)?;
 
         info!("MQTT client started");
         thread::spawn(move || {
diff --git a/src/voltage_detection.rs b/src/voltage_detection.rs
new file mode 100644
index 0000000..77213d1
--- /dev/null
+++ b/src/voltage_detection.rs
@@ -0,0 +1,124 @@
+use std::{
+    sync::{Arc, Mutex},
+    time::Duration,
+};
+
+use embedded_hal::{adc::Channel, prelude::_embedded_hal_adc_OneShot, digital::v2::OutputPin};
+use embedded_svc::timer::{PeriodicTimer, TimerService};
+use esp_idf_hal::{
+    adc::{
+        config::{self},
+        Analog, PoweredAdc, ADC1,
+    },
+    gpio::{Gpio1, Gpio2, Gpio3, Input, Pull},
+};
+use esp_idf_svc::timer::{EspTimer, EspTimerService};
+use log::{info, warn};
+
+pub struct VoltageDetection {
+    pub worker: VoltageDetectionWorker,
+    watch_timer: Option<EspTimer>,
+}
+
+#[derive(Clone, Copy)]
+pub struct VoltageDetectionWorker {
+    pub adapter_voltage: u16,
+    pub battery_voltage: u16,
+    pub output_voltage: u16,
+}
+
+impl VoltageDetection {
+    pub fn new() -> Self {
+        return Self {
+            worker: VoltageDetectionWorker::new(),
+            watch_timer: None,
+        };
+    }
+
+    pub fn watching(&mut self) -> anyhow::Result<()> {
+        let worker = Arc::new(Mutex::new(self.worker));
+        let mut timer = EspTimerService::new()?.timer(move || {
+            info!("One-shot timer triggered");
+            match worker.as_ref().lock().as_mut() {
+                Ok(worker) => {
+                    if let Err(err) = worker.read_once() {
+                        warn!("Read Failed. {}", err);
+                    }
+                    info!(
+                        "Adapter: {},\tBattery: {},\t Output: {}",
+                        worker.adapter_voltage, worker.battery_voltage, worker.output_voltage
+                    );
+                }
+                Err(err) => {
+                    warn!("Lock VoltageDetection Worker Failed. {}", err)
+                }
+            }
+        })?;
+        timer.every(Duration::from_secs(1))?;
+
+        self.watch_timer = Some(timer);
+        return anyhow::Ok(());
+    }
+}
+impl VoltageDetectionWorker {
+    pub fn new() -> Self {
+        return Self {
+            adapter_voltage: 0,
+            battery_voltage: 0,
+            output_voltage: 0,
+        };
+    }
+
+    pub fn read_once(&mut self) -> anyhow::Result<()> {
+        let adapter_pin = unsafe { Gpio1::<Input>::new() }
+            .into_analog_atten_11db()
+            .map_err(|err| anyhow::anyhow!("Failed to set GPIO 1 as analog input. {}", err))?;
+        match self.read_pin_once(adapter_pin) {
+            Ok(voltage) => {
+                self.adapter_voltage = voltage;
+            }
+            Err(err) => {
+                warn!("Adapter Voltage read failed: {:?}", err);
+            }
+        }
+
+        let battery_pin = unsafe { Gpio2::<Input>::new() }
+            .into_analog_atten_11db()
+            .map_err(|err| anyhow::anyhow!("Failed to set GPIO 1 as analog input. {}", err))?;
+        match self.read_pin_once(battery_pin) {
+            Ok(voltage) => {
+                self.battery_voltage = voltage;
+            }
+            Err(err) => {
+                warn!("Adapter Voltage read failed: {:?}", err);
+            }
+        }
+
+        let output_pin = unsafe { Gpio3::<Input>::new() }
+            .into_analog_atten_11db()
+            .map_err(|err| anyhow::anyhow!("Failed to set GPIO 1 as analog input. {}", err))?;
+        match self.read_pin_once(output_pin) {
+            Ok(voltage) => {
+                self.output_voltage = voltage;
+            }
+            Err(err) => {
+                warn!("Adapter Voltage read failed: {:?}", err);
+            }
+        }
+
+        return anyhow::Ok(());
+    }
+    pub fn read_pin_once<AN: Analog<ADC1>, PIN: Channel<AN, ID = u8>>(
+        &mut self,
+        mut pin: PIN,
+    ) -> anyhow::Result<u16> {
+        let mut adc = PoweredAdc::new(unsafe { ADC1::new() }, config::Config::new())?;
+        let voltage = adc.read(&mut pin);
+        match voltage {
+            Ok(voltage) => anyhow::Ok((self.adapter_voltage + voltage * 10) / 11),
+            Err(err) => {
+                anyhow::bail!("Adapter Voltage read failed: {:?}", err)
+            }
+        }
+    }
+}