diff --git a/src/simulator/machine.rs b/src/simulator/machine.rs
index 2cc98ad..116a942 100644
--- a/src/simulator/machine.rs
+++ b/src/simulator/machine.rs
@@ -1,10 +1,15 @@
-use std::{ops::{Add, Sub}, io::Write};
-
-use crate::simulator::{print, error::MachineError};
-
-use super::{decode::{Instruction, decode}, interrupt::Interrupt};
-use super::global::*;
-use std::fs::File;
+use std::{
+	io::Write,
+	fs::File
+};
+use crate::simulator::{
+	print,
+	error::MachineError,
+	decode::*,
+	interrupt::Interrupt,
+	global::*,
+	register::*
+};
 
 /// Exceptions
 /// todo: is this really supposed to stand in machine.rs?
@@ -39,59 +44,6 @@ pub const PAGE_SIZE : u64 = 128;
 /// Must be a multiple of PAGE_SIZE
 pub const MEM_SIZE : usize = (PAGE_SIZE*NUM_PHY_PAGE*100) as usize;
 
-pub trait RegisterNum: Add<Output=Self> + Sub<Output=Self> + PartialEq + Copy {}
-
-impl RegisterNum for i64 {}
-
-impl RegisterNum for f32 {}
-
-
-#[derive(PartialEq)]
-pub struct Register<U: RegisterNum> {
-	register: [U; 32]
-}
-
-impl<U: RegisterNum> Register<U> {
-
-	pub fn get_reg(&self, position: u8) -> U {
-		self.register[position as usize]
-	}
-
-}
-
-impl Register<i64> {
-
-	pub fn init() -> Register<i64> {
-		Register { 
-			register: [0i64; 32]
-		}
-	}
-
-	pub fn set_reg(&mut self, position: usize, value: i64) {
-		if position != 0 {
-			self.register[position] = value;
-		} else {
-			// Panic ou rien ? (dans le doute pour le moment panic)
-			// unreachable!("You can't write to zero register")
-		}
-	}
-
-}
-
-impl Register<f32> {
-
-	pub fn init() -> Register<f32> {
-		Register { 
-			register: [0f32; 32]
-		}
-	}
-
-	pub fn set_reg(&mut self, position: usize, value: f32) {
-		self.register[position] = value;
-	}
-
-}
-
 #[derive(PartialEq)]
 pub struct Machine {
 	pub pc : u64,
diff --git a/src/simulator/mod.rs b/src/simulator/mod.rs
index e13df71..956ee64 100644
--- a/src/simulator/mod.rs
+++ b/src/simulator/mod.rs
@@ -7,6 +7,7 @@ pub mod loader;
 pub mod interrupt;
 pub mod translationtable;
 pub mod mmu;
+pub mod register;
 
 pub mod global {
 
diff --git a/src/simulator/register.rs b/src/simulator/register.rs
new file mode 100644
index 0000000..d352d74
--- /dev/null
+++ b/src/simulator/register.rs
@@ -0,0 +1,51 @@
+use std::ops::{Add,  Sub};
+
+pub trait RegisterNum: Add<Output=Self> + Sub<Output=Self> + PartialEq + Copy {}
+
+impl RegisterNum for i64 {}
+
+impl RegisterNum for f32 {}
+
+/// Machine register array
+#[derive(PartialEq)]
+pub struct Register<U: RegisterNum> {
+	/// 32 available registers of type U
+	register: [U; 32]
+}
+
+impl<U: RegisterNum> Register<U> {
+
+	/// Returns the current value held in register *position*
+	pub fn get_reg(&self, position: u8) -> U {
+		self.register[position as usize]
+	}
+
+	/// Set value of register *position* to *value* 
+	pub fn set_reg(&mut self, position: usize, value: U) {
+		self.register[position] = value;
+	}
+
+
+}
+
+impl Register<i64> {
+
+	/// i64 register constructor
+	pub fn init() -> Register<i64> {
+		Register { 
+			register: [0i64; 32]
+		}
+	}
+
+}
+
+impl Register<f32> {
+
+	/// f32 register constructor
+	pub fn init() -> Register<f32> {
+		Register { 
+			register: [0f32; 32]
+		}
+	}
+
+}
\ No newline at end of file