diff --git a/firmware/Cargo.toml b/firmware/Cargo.toml
index 5508bac..8d426a5 100644
--- a/firmware/Cargo.toml
+++ b/firmware/Cargo.toml
@@ -26,3 +26,4 @@ cheapsdo-protocol = { path = "../protocol" }
 postcard = {version = "1.0.8", features = ["use-defmt"]} 
 heapless = {version = "0.8.0", features = ["defmt-03"]}
 num = {version = "0.4.1", default-features = false, features = ["libm"]}
+serde = { version = "1.0.195", default-features = false }
diff --git a/firmware/src/main.rs b/firmware/src/main.rs
index 6ba8ba9..96b7a62 100644
--- a/firmware/src/main.rs
+++ b/firmware/src/main.rs
@@ -6,6 +6,7 @@ use defmt_rtt as _; // global logger
 use panic_probe as _;
 use stm32f1xx_hal as _;
 
+mod nvstate;
 mod si5153;
 
 // same panicking *behavior* as `panic-probe` but doesn't print a panic message
@@ -24,6 +25,7 @@ mod app {
     use rtic_monotonics::systick::*;
 
     use stm32f1xx_hal::{
+        flash::{self, FlashWriter},
         gpio::{self, gpioa, gpioc, Alternate, Output, PushPull},
         i2c, pac,
         pac::{RCC, TIM2, TIM3, TIM4},
@@ -41,6 +43,7 @@ mod app {
 
     use cheapsdo_protocol::{DeviceMessage, HostMessage, StatusMessage};
 
+    use crate::nvstate::{self, NVState};
     use crate::si5153;
 
     const USB_BUFFER_SIZE: usize = 64;
@@ -51,6 +54,8 @@ mod app {
         tim2: TIM2,
         tim3: TIM3,
         pwm: PwmHz<TIM4, Tim4NoRemap, timer::Ch<0>, gpio::Pin<'B', 6, Alternate>>,
+        nvstate: NVState,
+        flash: flash::Parts,
     }
 
     #[shared]
@@ -229,6 +234,10 @@ mod app {
         si_pll.set_ms_freq(&mut i2c1, si5153::Multisynth::MS0, 100_000_000);
         si_pll.enable_ms_output(&mut i2c1, si5153::Multisynth::MS0);
 
+        let nvstate = nvstate::load(&mut flash);
+
+        defmt::info!("read nvstate from flash");
+
         update_pwm::spawn().unwrap();
 
         (
@@ -243,13 +252,15 @@ mod app {
                 tim2,
                 tim3,
                 pwm,
+                nvstate,
+                flash,
             },
         )
     }
 
     const WINDOW_LEN: usize = 100;
 
-    #[task(local=[tim2, tim3, pwm, board_led], shared=[device_status])]
+    #[task(local=[tim2, tim3, pwm, board_led, nvstate, flash], shared=[device_status])]
     async fn update_pwm(mut cx: update_pwm::Context) {
         defmt::info!("Update Task started");
 
@@ -257,9 +268,16 @@ mod app {
         let tim3 = cx.local.tim3;
         let pwm = cx.local.pwm;
         let board_led = cx.local.board_led;
+        let mut nvstate = cx.local.nvstate;
+        let mut flash = cx.local.flash;
 
         let max_pwm = pwm.get_max_duty() as i32;
-        let mut cur_pwm = max_pwm / 2;
+        let mut cur_pwm = nvstate.pwm as i32;
+        cur_pwm = if cur_pwm < 0 { 0 } else { cur_pwm };
+        cur_pwm = if cur_pwm > max_pwm { max_pwm } else { cur_pwm };
+
+        pwm.set_duty(Channel::C1, cur_pwm as u16);
+        defmt::info!("pwm:\t{}", cur_pwm);
 
         // Inialize last_ic
         while !tim2.sr.read().cc1if().bit_is_set() || !tim3.sr.read().cc1if().bit_is_set() {
@@ -343,6 +361,9 @@ mod app {
             pwm.set_duty(Channel::C1, cur_pwm as u16);
             defmt::info!("pwm:\t{}", cur_pwm);
 
+            nvstate.pwm = cur_pwm as u16;
+            nvstate.save(&mut flash);
+
             Systick::delay(500.millis()).await;
         }
     }
diff --git a/firmware/src/nvstate.rs b/firmware/src/nvstate.rs
new file mode 100644
index 0000000..e9b6ead
--- /dev/null
+++ b/firmware/src/nvstate.rs
@@ -0,0 +1,45 @@
+use postcard::{from_bytes_cobs, to_slice_cobs};
+use serde::{Deserialize, Serialize};
+use stm32f1xx_hal::flash::{self, FlashSize, FlashWriter, SectorSize};
+
+#[derive(Serialize, Deserialize, Debug, PartialEq)]
+pub struct NVState {
+    pub pwm: u16,
+}
+
+impl Default for NVState {
+    fn default() -> Self {
+        Self { pwm: 1500u16 }
+    }
+}
+
+const PAGE_SIZE: usize = 1024;
+const NVSTATE_OFFSET: u32 = 63 * PAGE_SIZE as u32;
+
+const FLASH_SIZE: FlashSize = FlashSize::Sz64K;
+const SECTOR_SIZE: SectorSize = SectorSize::Sz1K;
+
+pub fn load(flash: &mut flash::Parts) -> NVState {
+    let mut flash_writer = flash.writer(SECTOR_SIZE, FLASH_SIZE);
+
+    let tmp = flash_writer.read(NVSTATE_OFFSET, PAGE_SIZE).unwrap();
+    let mut nvstate_page = [0u8; PAGE_SIZE];
+    nvstate_page.copy_from_slice(tmp);
+
+    match from_bytes_cobs::<NVState>(&mut nvstate_page) {
+        Ok(nvstate) => nvstate,
+        Err(_) => NVState::default(),
+    }
+}
+
+impl NVState {
+    pub fn save(&self, flash: &mut flash::Parts) {
+        let mut flash_writer = flash.writer(SECTOR_SIZE, FLASH_SIZE);
+
+        let mut page = [0u8; PAGE_SIZE];
+        let used = to_slice_cobs(self, &mut page).unwrap();
+
+        flash_writer.page_erase(NVSTATE_OFFSET).unwrap();
+        flash_writer.write(NVSTATE_OFFSET, &used).unwrap();
+    }
+}
diff --git a/memory.x b/memory.x
index 71f245d..ab4c50c 100644
--- a/memory.x
+++ b/memory.x
@@ -1,6 +1,7 @@
 /* Linker script for the STM32F103C8T6 */
 MEMORY
 {
-  FLASH : ORIGIN = 0x08000000, LENGTH = 64K
+  FLASH : ORIGIN = 0x08000000, LENGTH = 63K
+  NVSTATE : ORIGIN = FLASH + 63K, LENGTH = 1K
   RAM : ORIGIN = 0x20000000, LENGTH = 20K
 }