diff --git a/Cargo.lock b/Cargo.lock
index ce4f182..3764ad5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -42,7 +42,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bcb2392079bf27198570d6af79ecbd9ec7d8f16d3ec6b60933922fdb66287127"
 dependencies = [
  "heapless",
- "nom 4.2.3",
+ "nom",
 ]
 
 [[package]]
@@ -74,6 +74,7 @@ dependencies = [
  "bitflags",
  "cortex-m",
  "embedded-hal",
+ "embedded-sdmmc",
  "modular-bitfield",
  "nb 1.1.0",
  "num-traits",
@@ -341,12 +342,14 @@ dependencies = [
 
 [[package]]
 name = "embedded-sdmmc"
-version = "0.5.0"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2f4d14180a76a8af24a45a0e1a4f9c97491b05a3b962d59d5e4ce0e6ab103736"
+checksum = "6d3bf0a2b5becb87e9a329d9290f131e4d10fec39b56d129926826a7cbea1e7a"
 dependencies = [
  "byteorder",
  "embedded-hal",
+ "log",
+ "nb 0.1.3",
 ]
 
 [[package]]
@@ -530,6 +533,7 @@ version = "0.10.0"
 dependencies = [
  "atsamd-hal",
  "cortex-m-rt",
+ "embedded-sdmmc",
  "usb-device",
 ]
 
@@ -619,16 +623,6 @@ dependencies = [
  "version_check 0.1.5",
 ]
 
-[[package]]
-name = "nom"
-version = "6.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c6a7a9657c84d5814c6196b68bb4429df09c18b1573806259fba397ea4ad0d44"
-dependencies = [
- "memchr",
- "version_check 0.9.4",
-]
-
 [[package]]
 name = "num-integer"
 version = "0.1.45"
@@ -832,8 +826,6 @@ dependencies = [
  "epd-waveshare",
  "maduino_zero_4g",
  "panic-halt",
- "tinybmp",
- "tinytga",
  "tz-rs",
  "tzdb",
 ]
@@ -939,25 +931,6 @@ dependencies = [
  "weezl",
 ]
 
-[[package]]
-name = "tinybmp"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0e959c507975d768a226a08227d56791f6e60bddcf714ad7ef67ae2d20bae743"
-dependencies = [
- "embedded-graphics",
-]
-
-[[package]]
-name = "tinytga"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "756dcc0078b35e5f8ab052f19a48225821fd046011342d31deef6b8d5c825d2b"
-dependencies = [
- "embedded-graphics",
- "nom 6.2.2",
-]
-
 [[package]]
 name = "typenum"
 version = "1.16.0"
diff --git a/Cargo.toml b/Cargo.toml
index 410c764..a067b98 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,12 +12,10 @@ atsamd-hal = { version = "0.15.1", default_features = false, features = ["samd21
 cfg-if = "1.0.0"
 embedded-graphics = "0.7.1"
 embedded-text = "0.5.0"
-embedded-sdmmc = { version = "0.5.0", default_features = false }
+embedded-sdmmc = { version = "0.3.0", default_features = false }
 epd-waveshare = "0.5.0"
 maduino_zero_4g = { git = "https://github.com/ZettaScript/atsamd", branch = "maduino-zero-4g", features = ["usb"] }
 panic-halt = "0.2.0"
-tinybmp = "0.4.0"
-tinytga = "0.4.1"
 tz-rs = { version = "0.6.14", default_features = false, features = ["const"] }
 tzdb = { version = "0.5.7", optional = true }
 
@@ -31,6 +29,7 @@ simulator = ["embedded-graphics-simulator", "tzdb"]
 
 [profile.release]
 lto = "fat"
+opt-level = 3
 
 [patch."https://github.com/ZettaScript/atsamd"]
 maduino_zero_4g = { path = "../atsamd/boards/maduino_zero_4g" }
diff --git a/README.md b/README.md
index 9452945..a437930 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ rustup target add thumbv6m-none-eabi
 ## Run simulator
 
 ```bash
-cargo run
+cargo run --features simulator
 ```
 
 ## Build
@@ -59,7 +59,7 @@ Note: at most 5 outputs of the 74HC565 may be used as GPO.
 https://www.makerfabs.com/maduino-zero-4g-lte-sim7600.html
 https://www.waveshare.com/1.54inch-e-Paper-Module.htm1
 https://bulkmemorycards.com/shop/microsd-cards/microsd-32gb/sd-32gb-class-10/32gb-microsd-ultra-sandisk-memory-card-2/
-Maybe an ESP for WIFI and Bluetooth.
+Maybe an ESP for WIFI and Bluetooth: https://www.sparkfun.com/products/18034
 
 ## crates
 bitmap-font ?
diff --git a/src/apps.rs b/src/apps.rs
index 9946f8a..0cd1ff3 100644
--- a/src/apps.rs
+++ b/src/apps.rs
@@ -1,9 +1,11 @@
-use crate::display::Display;
+use crate::{display::Display, keypad::KeyEvents, state::ModeState, Context};
 
+pub mod clock;
 pub mod dial;
 
 pub trait App {
-	type State;
+	type AppModeState;
 
-	fn update(display: &mut Display);
+	/// Return Some if the mode should be changed
+	fn update(context: &mut Context, mode_state: &mut Self::AppModeState) -> Option<ModeState>;
 }
diff --git a/src/apps/clock.rs b/src/apps/clock.rs
new file mode 100644
index 0000000..2bdcc4d
--- /dev/null
+++ b/src/apps/clock.rs
@@ -0,0 +1,112 @@
+use crate::{
+	apps,
+	apps::App,
+	display::Display,
+	keypad::*,
+	state::{self, ModeState},
+	strf, Context,
+};
+
+use arrayvec::ArrayString;
+use embedded_graphics::{
+	mono_font::{ascii::FONT_10X20, MonoTextStyleBuilder},
+	pixelcolor::BinaryColor,
+	prelude::*,
+	text::{Alignment, Text},
+};
+
+pub struct Clock;
+
+pub struct ClockState {
+	year: i32,
+	month: u8,
+	day: u8,
+	week_day: u8,
+}
+
+impl Default for ClockState {
+	fn default() -> Self {
+		Self {
+			year: 0,
+			month: 0,
+			day: 0,
+			week_day: 0,
+		}
+	}
+}
+
+impl App for Clock {
+	type AppModeState = ClockState;
+
+	fn update(ctx: &mut Context, mode_state: &mut ClockState) -> Option<ModeState> {
+		// TODO move at init
+		let clock_text_style = MonoTextStyleBuilder::new()
+			.font(&FONT_10X20)
+			.text_color(BinaryColor::On)
+			.background_color(BinaryColor::Off)
+			.build();
+
+		for key_event in &ctx.key_events {
+			if key_event.event_type != KeyEventType::Pressed {
+				continue;
+			}
+			match key_event.key {
+				_ => {
+					if let Some(ch) = key_event.get_char(KeyInputMode::Digit) {
+						let mut buf = [0; 4];
+						return Some(ModeState::Dial(apps::dial::DialState {
+							line: ArrayString::from(&*ch.encode_utf8(&mut buf)).unwrap(),
+						}));
+					}
+				}
+			}
+		}
+
+		if ctx.hm_change {
+			Text::with_alignment(
+				unsafe {
+					core::str::from_utf8_unchecked(&strf::fmt_time_hm(
+						ctx.state.hour,
+						ctx.state.minute,
+					))
+				},
+				ctx.display.inner().bounding_box().center() + Point::new(0, 10),
+				clock_text_style,
+				Alignment::Center,
+			)
+			.draw(ctx.display.inner_mut())
+			.unwrap();
+
+			let year_ = ctx.now.year();
+			let month_ = ctx.now.month();
+			let day_ = ctx.now.month_day();
+			let week_day_ = ctx.now.week_day();
+			if (year_, month_, day_, week_day_)
+				!= (
+					mode_state.year,
+					mode_state.month,
+					mode_state.day,
+					mode_state.week_day,
+				) {
+				mode_state.year = year_;
+				mode_state.month = month_;
+				mode_state.day = day_;
+				mode_state.week_day = week_day_;
+				Text::with_alignment(
+					unsafe {
+						core::str::from_utf8_unchecked(&strf::fmt_time_ymdw(
+							year_, month_, day_, week_day_,
+						))
+					},
+					ctx.display.inner().bounding_box().center() + Point::new(0, -20),
+					clock_text_style,
+					Alignment::Center,
+				)
+				.draw(ctx.display.inner_mut())
+				.unwrap();
+			}
+		}
+
+		None
+	}
+}
diff --git a/src/apps/dial.rs b/src/apps/dial.rs
index 8b13789..6ec8335 100644
--- a/src/apps/dial.rs
+++ b/src/apps/dial.rs
@@ -1 +1,45 @@
+use crate::{
+	apps::App,
+	display::Display,
+	keypad::{Key, KeyEvent, KeyEventType, KeyEvents, KeyInputMode},
+	state::{ModeState, State},
+	Context,
+};
 
+use arrayvec::ArrayString;
+
+pub struct Dial;
+
+pub struct DialState {
+	// TODO what should max length be?
+	pub line: ArrayString<255>,
+}
+
+impl App for Dial {
+	type AppModeState = DialState;
+
+	fn update(ctx: &mut Context, mode_state: &mut DialState) -> Option<ModeState> {
+		for key_event in &ctx.key_events {
+			if key_event.event_type != KeyEventType::Pressed {
+				continue;
+			}
+			match key_event.key {
+				Key::HangUp => {
+					return Some(ModeState::Clock(Default::default()));
+				}
+				Key::PickUp => {
+					// TODO
+				}
+				_ => {
+					if let Some(ch) = key_event.get_char(KeyInputMode::Digit) {
+						if mode_state.line.try_push(ch).is_err() {
+							// TODO
+						}
+					}
+				}
+			}
+		}
+
+		None
+	}
+}
diff --git a/src/fs.rs b/src/fs.rs
new file mode 100644
index 0000000..7d3f6eb
--- /dev/null
+++ b/src/fs.rs
@@ -0,0 +1,29 @@
+use atsamd_hal::{delay::Delay, pac::Peripherals, prelude::*, sercom::spi::EightBit};
+use embedded_sdmmc::{Controller, SdMmcSpi, VolumeIdx};
+
+pub struct Fs {
+	controller: Controller<SdMmcSpi<maduino_zero_4g::SdSpi, maduino_zero_4g::SdCs>, ClockMock>,
+}
+
+impl Fs {
+	pub fn new(spi: maduino_zero_4g::SdSpi, cs: maduino_zero_4g::SdCs) -> Self {
+		let controller = Controller::new(SdMmcSpi::new(spi, cs), ClockMock);
+		Self { controller }
+	}
+}
+
+struct ClockMock;
+
+// TODO
+impl embedded_sdmmc::TimeSource for ClockMock {
+	fn get_timestamp(&self) -> embedded_sdmmc::Timestamp {
+		embedded_sdmmc::Timestamp {
+			year_since_1970: 0,
+			zero_indexed_month: 0,
+			zero_indexed_day: 0,
+			hours: 0,
+			minutes: 0,
+			seconds: 0,
+		}
+	}
+}
diff --git a/src/gui.rs b/src/gui.rs
index 8b13789..51be9a0 100644
--- a/src/gui.rs
+++ b/src/gui.rs
@@ -1 +1 @@
-
+pub trait Widget {}
diff --git a/src/keypad.rs b/src/keypad.rs
index a43be6d..c2300c6 100644
--- a/src/keypad.rs
+++ b/src/keypad.rs
@@ -4,6 +4,8 @@ const NB_KEYS: usize = 21;
 /// Key repeat max delay (ms)
 const REPEAT_DELAY: u64 = 500;
 
+pub type KeyEvents = ArrayVec<KeyEvent, 4>;
+
 pub struct Keypad {
 	last_key: Option<(Key, u64, u8)>,
 	pressed: [bool; NB_KEYS],
@@ -19,7 +21,7 @@ impl Default for Keypad {
 }
 
 impl Keypad {
-	pub fn update(&mut self) -> ArrayVec<KeyEvent, 4> {
+	pub fn update(&mut self) -> KeyEvents {
 		self.get_keys()
 			.into_iter()
 			.zip(self.pressed.iter_mut())
@@ -97,7 +99,7 @@ impl Keypad {
 			.for_each(|key| keys[key as usize] = true);
 		keys
 	}
-	
+
 	#[cfg(not(feature = "simulator"))]
 	fn get_keys(&self) -> [bool; NB_KEYS] {
 		[false; NB_KEYS]
@@ -137,26 +139,41 @@ impl Key {
 }
 
 pub struct KeyEvent {
-	event_type: KeyEventType,
-	key: Key,
-	repeats: u8,
+	pub event_type: KeyEventType,
+	pub key: Key,
+	pub repeats: u8,
 }
 
-/*impl KeyEvent {
+impl KeyEvent {
 	pub fn get_char(&self, key_input_mode: KeyInputMode) -> Option<char> {
 		use Key::*;
 		match key_input_mode {
-			
 			KeyInputMode::Digit => match self.key {
-				D0 => 
+				D0 => Some('0'),
+				D1 => Some('1'),
+				D2 => Some('2'),
+				D3 => Some('3'),
+				D4 => Some('4'),
+				D5 => Some('5'),
+				D6 => Some('6'),
+				D7 => Some('7'),
+				D8 => Some('8'),
+				D9 => Some('9'),
+				Asterisk => Some('*'),
+				Hash => Some('#'),
+				_ => None,
+			},
+			_ => {
+				None /* TODO */
 			}
 		}
 	}
-}*/
+}
 //ncb1	upz2	tdk3
 //eow4	lqh5	age6
 //sfx7	rmj8	ivy9
 
+#[derive(Eq, PartialEq)]
 pub enum KeyEventType {
 	Pressed,
 	Down,
diff --git a/src/main.rs b/src/main.rs
index c574795..26ed54b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -5,25 +5,19 @@ mod apps;
 mod config;
 mod display;
 mod energy;
+mod fs;
 mod gui;
 mod keypad;
 mod state;
 mod strf;
 mod time;
 
+use apps::App;
+use display::Display;
 use energy::EnergyStatus;
+use keypad::KeyEvents;
 use state::*;
 
-cfg_if::cfg_if! {
-	if #[cfg(not(feature = "simulator"))] {
-		use maduino_zero_4g as bsp;
-		use bsp::hal;
-		
-		use hal::pac::{CorePeripherals, Peripherals};
-		use hal::prelude::*;
-	}
-}
-
 use arrayvec::ArrayString;
 use core::fmt::Write;
 use embedded_graphics::{
@@ -33,36 +27,55 @@ use embedded_graphics::{
 	primitives::{Line, PrimitiveStyle, PrimitiveStyleBuilder, Rectangle, StrokeAlignment},
 	text::{Alignment, Text},
 };
-
 #[cfg(not(feature = "simulator"))]
-use panic_halt as _;
-
-static mut STATE: State = State {
-	energy: EnergyStatus {
-		battery: 255,
-		charging: false,
-	},
-	hour: 0,
-	minute: 0,
-	mode: Mode::Clock {
-		year: 0,
-		month: 0,
-		day: 0,
-		week_day: 0,
+use maduino_zero_4g::{
+	self as bsp,
+	hal::{
+		clock::GenericClockController,
+		delay::Delay,
+		pac::{CorePeripherals, Peripherals},
+		prelude::*,
 	},
 };
-
-fn state() -> &'static State {
-	unsafe { &STATE }
-}
-
-fn state_mut() -> &'static mut State {
-	unsafe { &mut STATE }
-}
+#[cfg(not(feature = "simulator"))]
+use panic_halt as _;
+use tz::DateTime;
 
 #[cfg_attr(not(feature = "simulator"), bsp::entry)]
 fn main() -> ! {
-	let mut display = display::Display::new();
+	cfg_if::cfg_if! {
+		if #[cfg(not(feature = "simulator"))] {
+			let mut peripherals = Peripherals::take().unwrap();
+			let mut pins = maduino_zero_4g::Pins::new(peripherals.PORT);
+			let core = CorePeripherals::take().unwrap();
+			let mut clocks = GenericClockController::with_external_32kosc(
+				peripherals.GCLK,
+				&mut peripherals.PM,
+				&mut peripherals.SYSCTRL,
+				&mut peripherals.NVMCTRL,
+			);
+			let mut delay = Delay::new(core.SYST, &mut clocks);
+
+			let mut fs = fs::Fs::new(atsamd_hal::sercom::spi::Config::new(
+				&peripherals.PM,
+				peripherals.SERCOM4,
+				atsamd_hal::sercom::spi::Pads::default().data_in(pins.sd_miso).data_out(pins.sd_mosi).sclk(pins.sd_sck),
+				10_u32.mhz(),
+			).enable(), pins.d4.into_push_pull_output());
+		}
+	}
+
+	let mut state = State {
+		energy: EnergyStatus {
+			battery: 255,
+			charging: false,
+		},
+		hour: 0,
+		minute: 0,
+	};
+	let mut mode_state = ModeState::Clock(Default::default());
+
+	let mut display = Display::new();
 	let mut keypad = keypad::Keypad::default();
 
 	let thin_stroke = PrimitiveStyle::with_stroke(BinaryColor::On, 1);
@@ -73,11 +86,6 @@ fn main() -> ! {
 		.text_color(BinaryColor::On)
 		.background_color(BinaryColor::Off)
 		.build();
-	let clock_text_style = MonoTextStyleBuilder::new()
-		.font(&FONT_10X20)
-		.text_color(BinaryColor::On)
-		.background_color(BinaryColor::Off)
-		.build();
 
 	Line::new(Point::new(0, 13), Point::new(199, 13))
 		.into_styled(thin_stroke)
@@ -87,13 +95,19 @@ fn main() -> ! {
 	#[cfg(feature = "simulator")]
 	display.update();
 
-	let mut update = true;
-	let mut hm_change = true;
+	let mut ctx = Context {
+		display: &mut display,
+		hm_change: true,
+		key_events: Default::default(),
+		now: DateTime::from_timespec(0, 0, tz::TimeZoneRef::utc()).unwrap(),
+		update: true,
+		state: &mut state,
+	};
 	loop {
 		let energy_status = energy::get_energy_status();
 
-		if energy_status != state().energy {
-			update = true;
+		if energy_status != ctx.state.energy {
+			ctx.update = true;
 
 			Text::with_alignment(
 				unsafe { core::str::from_utf8_unchecked(&strf::fmt_energy(&energy_status)) },
@@ -101,21 +115,21 @@ fn main() -> ! {
 				statusbar_text_style,
 				Alignment::Left,
 			)
-			.draw(display.inner_mut())
+			.draw(ctx.display.inner_mut())
 			.unwrap();
 
-			state_mut().energy = energy_status;
+			ctx.state.energy = energy_status;
 		}
 
-		let now = time::now();
+		ctx.now = time::now();
 
-		let hour = now.hour();
-		let minute = now.minute();
-		if (hour, minute) != (state().hour, state().minute) {
-			update = true;
-			hm_change = true;
-			state_mut().hour = hour;
-			state_mut().minute = minute;
+		let hour = ctx.now.hour();
+		let minute = ctx.now.minute();
+		if (hour, minute) != (ctx.state.hour, ctx.state.minute) {
+			ctx.update = true;
+			ctx.hm_change = true;
+			ctx.state.hour = hour;
+			ctx.state.minute = minute;
 
 			Text::with_alignment(
 				unsafe { core::str::from_utf8_unchecked(&strf::fmt_time_hm(hour, minute)) },
@@ -123,67 +137,41 @@ fn main() -> ! {
 				statusbar_text_style,
 				Alignment::Right,
 			)
-			.draw(display.inner_mut())
+			.draw(ctx.display.inner_mut())
 			.unwrap();
 		}
 
-		let key_events = keypad.update();
+		ctx.key_events = keypad.update();
 
-		match &mut state_mut().mode {
-			Mode::Clock {
-				year,
-				month,
-				day,
-				week_day,
-			} => {
-				if hm_change {
-					Text::with_alignment(
-						unsafe { core::str::from_utf8_unchecked(&strf::fmt_time_hm(hour, minute)) },
-						display.inner().bounding_box().center() + Point::new(0, 10),
-						clock_text_style,
-						Alignment::Center,
-					)
-					.draw(display.inner_mut())
-					.unwrap();
-
-					let year_ = now.year();
-					let month_ = now.month();
-					let day_ = now.month_day();
-					let week_day_ = now.week_day();
-					if (year_, month_, day_, week_day_) != (*year, *month, *day, *week_day) {
-						*year = year_;
-						*month = month_;
-						*day = day_;
-						*week_day = week_day_;
-						Text::with_alignment(
-							unsafe {
-								core::str::from_utf8_unchecked(&strf::fmt_time_ymdw(
-									year_, month_, day_, week_day_,
-								))
-							},
-							display.inner().bounding_box().center() + Point::new(0, -20),
-							clock_text_style,
-							Alignment::Center,
-						)
-						.draw(display.inner_mut())
-						.unwrap();
-					}
-				}
-			}
+		if let Some(new_mode_state) = match &mut mode_state {
+			ModeState::Clock(clock_state) => apps::clock::Clock::update(&mut ctx, clock_state),
+			ModeState::Dial(dial_state) => apps::dial::Dial::update(&mut ctx, dial_state),
+		} {
+			mode_state = new_mode_state;
 		}
 
 		#[cfg(feature = "simulator")]
 		{
-			display.update();
+			ctx.display.update();
 			std::thread::sleep(core::time::Duration::from_millis(50));
 		}
 		#[cfg(not(feature = "simulator"))]
-		if update {
-			display.update();
+		if ctx.update {
+			ctx.display.update();
 		}
-		// TODO sleep on samd
+		#[cfg(not(feature = "simulator"))]
+		delay.delay_ms(50_u8);
 
-		update = false;
-		hm_change = false;
+		ctx.update = false;
+		ctx.hm_change = false;
 	}
 }
+
+pub struct Context<'a> {
+	pub state: &'a mut State,
+	pub display: &'a mut Display,
+	pub hm_change: bool,
+	pub now: DateTime,
+	pub update: bool,
+	pub key_events: KeyEvents,
+}
diff --git a/src/state.rs b/src/state.rs
index 0b32aee..76bc7c5 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -1,18 +1,18 @@
-use crate::energy::EnergyStatus;
+use crate::{apps, energy::EnergyStatus};
+
+/*pub struct State {
+	pub global: GlobalState,
+	pub mode: ModeState,
+}*/
 
-/// Global state
 pub struct State {
 	pub energy: EnergyStatus,
 	pub hour: u8,
 	pub minute: u8,
-	pub mode: Mode,
 }
 
-pub enum Mode {
-	Clock {
-		year: i32,
-		month: u8,
-		day: u8,
-		week_day: u8,
-	},
+#[warn(clippy::large_enum_variant)]
+pub enum ModeState {
+	Clock(apps::clock::ClockState),
+	Dial(apps::dial::DialState),
 }
diff --git a/src/strf.rs b/src/strf.rs
index 0d3e874..7252f8c 100644
--- a/src/strf.rs
+++ b/src/strf.rs
@@ -1,5 +1,3 @@
-use tz::DateTime;
-
 use crate::energy::EnergyStatus;
 
 static WEEK_DAYS: [[u8; 3]; 7] = [