diff --git a/blink/Cargo.lock b/blink/Cargo.lock
index 5929913..69bd93a 100644
--- a/blink/Cargo.lock
+++ b/blink/Cargo.lock
@@ -4,6 +4,7 @@ version = "0.1.0"
 dependencies = [
  "arduino 0.1.0",
  "core 0.1.0",
+ "rustc_builtins 0.1.0",
 ]
 
 [[package]]
@@ -17,3 +18,10 @@ dependencies = [
 name = "core"
 version = "0.1.0"
 
+[[package]]
+name = "rustc_builtins"
+version = "0.1.0"
+dependencies = [
+ "core 0.1.0",
+]
+
diff --git a/blink/Cargo.toml b/blink/Cargo.toml
index a51c25a..62ffa62 100644
--- a/blink/Cargo.toml
+++ b/blink/Cargo.toml
@@ -3,8 +3,21 @@ name = "blink"
 version = "0.1.0"
 authors = ["Jake Goulding <jake.goulding@gmail.com>"]
 
+[profile.release]
+lto = true
+
+# [dependencies]
+# rlibc = "*"
+
 [dependencies.core]
-path = "../libcore"
+path = "../rust-avr-libcore-mini"
 
 [dependencies.arduino]
 path = "../arduino"
+
+# [dependencies.compiler-rt]
+# git = "https://github.com/japaric/compiler-rt.rs"
+
+
+[dependencies.rustc_builtins]
+path = "/Users/shep/Projects/rustc-builtins"
diff --git a/blink/Makefile b/blink/Makefile
index 6115053..6bafb45 100644
--- a/blink/Makefile
+++ b/blink/Makefile
@@ -1,5 +1,6 @@
 COMPILED:=target/arduino/release/blink.elf
 HEX:=blink.hex
+SERIAL_PORT:=/dev/cu.usbmodem1411
 
 all: ${HEX}
 
@@ -14,4 +15,8 @@ ${HEX}: ${COMPILED}
 # Download the HEX to the board
 .PHONY: program
 program: ${HEX}
-	avrdude -p atmega328p -c arduino -P /dev/cu.usbmodem1411 -U flash:w:$<:i
+	avrdude -p atmega328p -c arduino -P ${SERIAL_PORT} -U flash:w:$<:i
+
+.PHONY: connect-terminal
+connect-terminal:
+	picocom ${SERIAL_PORT}
diff --git a/blink/arduino.json b/blink/arduino.json
index ee5bd27..87947eb 100644
--- a/blink/arduino.json
+++ b/blink/arduino.json
@@ -1,50 +1,58 @@
 {
   "llvm-target": "avr-atmel-none",
+  "cpu": "atmega328p",
+
   "target-endian": "little",
   "target-pointer-width": "16",
   "os": "none",
   "target-env": "gnu",
   "target-vendor": "unknown",
   "arch": "avr",
-  "data-layout": "e-p:16:8:8-i8:8:8-i16:8:8-i32:8:8-i64:8:8-f32:8:8-f64:8:8-n8",
+  "data-layout": "e-p:16:16:16-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-n8",
 
   "executables": true,
 
   "linker": "avr-gcc",
-  "pre-link-args": [
-    "-mmcu=atmega328p",
-    "-nostartfiles",
-    "../interrupt_vector.S"
-  ],
+  "linker-flavor": "gcc",
+  "pre-link-args": {
+    "gcc": [
+      "-mmcu=atmega328p",
+      "-nostartfiles",
+      "../interrupt_vector.S",
+      "../initialize_memory.S"
+    ]
+  },
   "exe-suffix": ".elf",
-  "post-link-args": [
-    "-Wl,--entry=main",
-    "-Wl,--entry=_ivr_irq0",
-    "-Wl,--entry=_ivr_irq1",
-    "-Wl,--entry=_ivr_pin_change_0",
-    "-Wl,--entry=_ivr_pin_change_1",
-    "-Wl,--entry=_ivr_pin_change_2",
-    "-Wl,--entry=_ivr_watchdog_timer",
-    "-Wl,--entry=_ivr_timer2_compare_a",
-    "-Wl,--entry=_ivr_timer2_compare_b",
-    "-Wl,--entry=_ivr_timer2_overflow",
-    "-Wl,--entry=_ivr_timer1_capture",
-    "-Wl,--entry=_ivr_timer1_compare_a",
-    "-Wl,--entry=_ivr_timer1_compare_b",
-    "-Wl,--entry=_ivr_timer1_overflow",
-    "-Wl,--entry=_ivr_timer0_compare_a",
-    "-Wl,--entry=_ivr_timer0_compare_b",
-    "-Wl,--entry=_ivr_timer0_overflow",
-    "-Wl,--entry=_ivr_spi_transfer_complete",
-    "-Wl,--entry=_ivr_usart_rx_complete",
-    "-Wl,--entry=_ivr_usart_udr_empty",
-    "-Wl,--entry=_ivr_usart_tx_complete",
-    "-Wl,--entry=_ivr_adc_conversion_complete",
-    "-Wl,--entry=_ivr_eeprom_ready",
-    "-Wl,--entry=_ivr_analog_comparator",
-    "-Wl,--entry=_ivr_two_wire_serial_interface",
-    "-Wl,--entry=_ivr_store_program_memory_ready"
-  ],
+  "post-link-args": {
+    "gcc": [
+      "-Wl,--entry=main",
+      "-Wl,--entry=_ivr_irq0",
+      "-Wl,--entry=_ivr_irq1",
+      "-Wl,--entry=_ivr_pin_change_0",
+      "-Wl,--entry=_ivr_pin_change_1",
+      "-Wl,--entry=_ivr_pin_change_2",
+      "-Wl,--entry=_ivr_watchdog_timer",
+      "-Wl,--entry=_ivr_timer2_compare_a",
+      "-Wl,--entry=_ivr_timer2_compare_b",
+      "-Wl,--entry=_ivr_timer2_overflow",
+      "-Wl,--entry=_ivr_timer1_capture",
+      "-Wl,--entry=_ivr_timer1_compare_a",
+      "-Wl,--entry=_ivr_timer1_compare_b",
+      "-Wl,--entry=_ivr_timer1_overflow",
+      "-Wl,--entry=_ivr_timer0_compare_a",
+      "-Wl,--entry=_ivr_timer0_compare_b",
+      "-Wl,--entry=_ivr_timer0_overflow",
+      "-Wl,--entry=_ivr_spi_transfer_complete",
+      "-Wl,--entry=_ivr_usart_rx_complete",
+      "-Wl,--entry=_ivr_usart_udr_empty",
+      "-Wl,--entry=_ivr_usart_tx_complete",
+      "-Wl,--entry=_ivr_adc_conversion_complete",
+      "-Wl,--entry=_ivr_eeprom_ready",
+      "-Wl,--entry=_ivr_analog_comparator",
+      "-Wl,--entry=_ivr_two_wire_serial_interface",
+      "-Wl,--entry=_ivr_store_program_memory_ready"
+    ]
+  },
 
   "no-compiler-rt": true
 }
diff --git a/blink/src/main.rs b/blink/src/main.rs
index e372dad..153f399 100644
--- a/blink/src/main.rs
+++ b/blink/src/main.rs
@@ -1,17 +1,22 @@
 #![feature(lang_items)]
 #![feature(no_core)]
 #![feature(asm)]
+#![feature(naked_functions)]
+#![feature(abi_avr_interrupt)]
 
 #![no_core]
 #![no_main]
 
+#[macro_use]
 extern crate core;
 extern crate arduino;
+extern crate rustc_builtins;
 
 use core::prelude::v1::*;
 use core::ptr::{read_volatile, write_volatile};
 // Let's pretend to have a standard library
-pub use core::{option, iter};
+pub use core::{option, iter, fmt, ops};
+use core::fmt::Write;
 
 use arduino::*;
 use arduino::prelude::*;
@@ -29,52 +34,214 @@ pub unsafe extern "avr-interrupt" fn _ivr_timer1_compare_a() {
 }
 
 const CPU_FREQUENCY_HZ: u64 = 16_000_000;
-const DESIRED_HZ_TIM1: f64 = 1.0;
-const TIM1_PRESCALER: u64 = 1024;
-const INTERRUPT_EVERY_1_HZ_1024_PRESCALER: u16 = ((CPU_FREQUENCY_HZ as f64 / (DESIRED_HZ_TIM1 * TIM1_PRESCALER as f64)) as u64 - 1) as u16;
+const CPU_RAM_BYTES: u16 = 2048;
 
-const DESIRED_HZ_TIM0: f64 = 30.0;
-const TIM0_PRESCALER: u64 = 1024;
-const INTERRUPT_EVERY_30_HZ_1024_PRESCALER: u8 = ((CPU_FREQUENCY_HZ as f64 / (DESIRED_HZ_TIM0 * TIM0_PRESCALER as f64)) as u64 - 1) as u8;
+const DESIRED_HZ_TIM1: f64 = 2.0;
+const TIM1_PRESCALER: u64 = 1024;
+const INTERRUPT_EVERY_1_HZ_1024_PRESCALER: u16 =
+    ((CPU_FREQUENCY_HZ as f64 / (DESIRED_HZ_TIM1 * TIM1_PRESCALER as f64)) as u64 - 1) as u16;
+
+// const DESIRED_HZ_TIM0: f64 = 30.0;
+// const TIM0_PRESCALER: u64 = 1024;
+// const INTERRUPT_EVERY_30_HZ_1024_PRESCALER: u8 = ((CPU_FREQUENCY_HZ as f64 / (DESIRED_HZ_TIM0 * TIM0_PRESCALER as f64)) as u64 - 1) as u8;
 
 const BAUD: u64 = 9600;
 const MYUBRR: u16 = (CPU_FREQUENCY_HZ / 16 / BAUD - 1) as u16;
 
-#[no_mangle]
-pub extern fn main() {
+// const MEMORY_MAP_START: u16 = MEMORY_MAP_REGISTERS_START;
+// const MEMORY_MAP_REGISTERS_START: u16 = 0x0000; // - 0x001F
+// const MEMORY_MAP_IO_REGISTERS_START: u16 = 0x0020; // - 0x005F
+// const MEMORY_MAP_EXTENDED_IO_REGISTERS_START: u16 = 0x0060; // - 0x00FF
+// const MEMORY_MAP_SRAM_START: u16 = 0x0100;
+// const MEMORY_MAP_SRAM_END: u16 = 0x0900; // EXCLUSIVE! DEPENDS ON PART!
+    // 0x02FF/0x04FF/0x4FF/0x08FF
+
+
+
+// extern {
+//     static __data_start: u16;
+//     static __data_end: u16;
+//     static __data_load_start: u16;
+//     static __data_load_end: u16;
+// }
+
+extern {
+    #[naked]
+    fn __initialize_memory();
+}
+
+fn initialize_memory() {
     unsafe {
-        without_interrupts(|| {
+        __initialize_memory();
+    }
+
+    // let len = __data_load_end - __data_load_start;
+    // if len == 0 { return }
+
+    // fn hi_lo(v: u16) -> (u8, u8) {
+    //     (((v >> 8) & 0xFF) as u8, ((v >> 0) & 0xFF) as u8)
+    // }
+
+    // let (len_hi, len_lo) = hi_lo(len);
+    // let (z_hi, z_lo) = hi_lo(__data_load_start);
+    // let (x_hi, x_lo) = hi_lo(__data_start);
+
+//     unsafe {
+//         asm!("
+//             sub r28, r30
+//             sbc r29, r31    ; Y now contains the length of bytes
+// entrypoint:
+//             lpm r0, Z+      ; Load from program memory, increment pointer
+//             st X+, r0       ; Store to RAM, increment pointer
+
+//             subi r28, 1     ; Decrement the count
+//             sbci r29, 0
+// check:
+//             brne entrypoint ; Exit when all bytes copied"
+//              : // output operands
+//              : // input operands
+//              "{r31r30}"(__data_load_start) // Z
+//              "{r27r26}"(__data_start)      // X
+//              "{r29r28}"(__data_load_end)   // Y
+//              : // clobbers
+//              "cc r0"
+//              : // options
+//         );
+
+        // let src = __data_start as *mut u8;
+        // let dest = __data_load_start as *mut u8;
+        // let len = __data_load_end - __data_load_start;
+
+        // let src = 00800100 as *mut u8;
+        // let dest = 00000126 as *mut u8;
+        // let len = 00000136 - 00000124;
+
+        // let dest = __data_start as *mut u8;
+        // let src = __data_load_start as *mut u8;
+        // let end = __data_load_end as *mut u8;
+
+        // 0x0118
+        //     0x0128
+
+
+}
+
+#[no_mangle]
+pub extern fn main() -> ! {
+    without_interrupts(|| { // TODO: we know interrupts are off, don't we?
+        // r1 is assumed to be always zero
+        unsafe { asm!("eor r1, r1"); }
+
+        unsafe {
+            write_volatile(SP, CPU_RAM_BYTES);
+        }
+
+        initialize_memory();
+
+        unsafe {
             // Configure all Port B pins as outputs
             write_volatile(DDRB, 0xFF);
             // Turn on all Port B pins
             write_volatile(PORTB, 0xFF);
+        }
 
-            timer0::Timer::new()
-                .waveform_generation_mode(timer0::WaveformGenerationMode::ClearOnTimerMatchOutputCompare)
-                .clock_source(timer0::ClockSource::Prescale1024)
-                .output_compare_1(Some(INTERRUPT_EVERY_30_HZ_1024_PRESCALER))
-                .configure();
+        timer1::Timer::new()
+            .waveform_generation_mode(timer1::WaveformGenerationMode::ClearOnTimerMatchOutputCompare)
+            .clock_source(timer1::ClockSource::Prescale1024)
+            .output_compare_1(Some(INTERRUPT_EVERY_1_HZ_1024_PRESCALER))
+            .configure();
 
-            timer1::Timer::new()
-                .waveform_generation_mode(timer1::WaveformGenerationMode::ClearOnTimerMatchOutputCompare)
-                .clock_source(timer1::ClockSource::Prescale1024)
-                .output_compare_1(Some(INTERRUPT_EVERY_1_HZ_1024_PRESCALER))
-                .configure();
+        serial::Serial::new(MYUBRR)
+            .character_size(serial::CharacterSize::EightBits)
+            .mode(serial::Mode::Asynchronous)
+            .parity(serial::Parity::Disabled)
+            .stop_bits(serial::StopBits::OneBit)
+            .configure();
+    });
 
-            serial::Serial::new(MYUBRR)
-                .character_size(serial::CharacterSize::EightBits)
-                .mode(serial::Mode::Asynchronous)
-                .parity(serial::Parity::Disabled)
-                .stop_bits(serial::StopBits::OneBit)
-                .configure();
-        });
+    serial::transmit(b'A');
 
-        for &b in b"hello, world!" {
+    write_newline();
+    for i in 0..4 {
+        let b = unsafe { *TO_HEX.get_unchecked(i) };
+        serial::transmit(b);
+    }
+    write_newline();
+
+    write_u8_hex(0x00);
+    write_newline();
+    write_u8_hex(0x05);
+    write_newline();
+    write_u8_hex(0x50);
+    write_newline();
+    write_u8_hex(0xFF);
+    write_newline();
+
+    write_slice_hex(&[0x00, 0x05, 0x50, 0xFF]);
+    write_newline();
+
+    write_raw("write_raw");
+
+    SuperSerial.write_str("write_str\r\n").unwrap();
+
+    // Formatting code disabled in libcore
+    writeln!(SuperSerial, "writeln!").unwrap();
+    write_newline();
+
+    serial::transmit(b'Z');
+    write_newline();
+
+    loop {
+        if let Some(b) = serial::try_receive() {
             serial::transmit(b);
+            serial::transmit(b'<');
         }
-
-        loop {
-            // forever!
-        }
+        // forever!
+    }
+}
+
+pub static TO_HEX: &'static [u8; 16] = b"0123456789ABCDEF";
+
+#[inline(never)]
+pub fn write_slice_hex(v: &[u8]) {
+    for &b in v {
+        write_u8_hex(b);
+    }
+}
+
+#[inline(never)]
+pub fn write_u8_hex(v: u8) {
+    let top_idx = (v >> 4) & 0b1111;
+    let bot_idx = (v >> 0) & 0b1111;
+
+    let top = unsafe { *TO_HEX.get_unchecked(top_idx as usize) };
+    let bot = unsafe { *TO_HEX.get_unchecked(bot_idx as usize) };
+
+    serial::transmit(top);
+    serial::transmit(bot);
+}
+
+#[inline(never)]
+fn write_newline() {
+    serial::transmit(b'\r');
+    serial::transmit(b'\n');
+}
+
+#[inline(never)]
+fn write_raw(s: &str) {
+    for b in s.bytes() {
+        serial::transmit(b);
+    }
+    write_newline();
+}
+
+struct SuperSerial;
+
+impl fmt::Write for SuperSerial {
+    fn write_str(&mut self, s: &str) -> Result<(), fmt::Error> {
+        for b in s.bytes() {
+            serial::transmit(b);
+        }
+        Ok(())
     }
 }
diff --git a/initialize_memory.S b/initialize_memory.S
new file mode 100644
index 0000000..ccd8bc8
--- /dev/null
+++ b/initialize_memory.S
@@ -0,0 +1,29 @@
+.section .text
+.globl __initialize_memory
+.type __initialize_memory, @function
+
+;;; Does not handle the region pointer!
+__initialize_memory:
+        ldi r31, hi8(__data_load_start)
+        ldi r30, lo8(__data_load_start)         ; Z
+
+        ldi r29, hi8(__data_load_end)
+        ldi r28, lo8(__data_load_end)           ; Y
+
+        ldi r27, hi8(__data_start)
+        ldi r26, lo8(__data_start)              ; X
+
+        sub r28, r30
+        sbc r29, r31    ; Y now contains the length of bytes
+        rjmp check
+
+entrypoint:
+        lpm r0, Z+      ; Load from program memory, increment pointer
+        st X+, r0       ; Store to RAM, increment pointer
+
+        subi r28, 1     ; Decrement the count
+        sbci r29, 0
+
+check:
+        brne entrypoint ; Exit when all bytes copied
+        ret
diff --git a/libcore/Cargo.toml b/libcore/Cargo.toml
index bc49df1..78d1a86 100644
--- a/libcore/Cargo.toml
+++ b/libcore/Cargo.toml
@@ -4,5 +4,5 @@ version = "0.1.0"
 authors = ["Jake Goulding <jake.goulding@gmail.com>"]
 
 [lib]
-#path = "/Users/shep/Projects/avr-rust/src/libcore/lib.rs"
-path = "/tmp/libcore/lib.rs"
+path = "/Users/shep/Projects/avr-rust/src/libcore/lib.rs"
+# path = "/tmp/libcore/lib.rs"