diff --git a/src/simulator/machine.rs b/src/simulator/machine.rs
index 000a1fe..e71328b 100644
--- a/src/simulator/machine.rs
+++ b/src/simulator/machine.rs
@@ -308,9 +308,9 @@ impl Machine {
 						},
 						RISCV_OP_SLT => {
 							if machine.int_reg[inst.rs1 as usize] < machine.int_reg[inst.rs2 as usize] {
-							machine.int_reg[inst.rd as usize] = 1;
+								machine.int_reg[inst.rd as usize] = 1;
 							} else {
-							machine.int_reg[inst.rd as usize] = 0;
+								machine.int_reg[inst.rd as usize] = 0;
 							}
 						},
 						RISCV_OP_SLTU => {
@@ -410,5 +410,20 @@ impl Machine {
 
 #[cfg(test)]
  mod test {
+    use crate::simulator::machine::Machine;
 
+	#[test]
+	fn test_read_memory() {
+		let mut m = Machine::_init_machine();
+    	m.main_memory[4] = 43;
+    	m.main_memory[5] = 150;
+		assert_eq!((43 << 8) + 150, Machine::read_memory(&mut m, 2, 4));
+	}
+
+	fn test_write_memory() {
+		let mut m = Machine::_init_machine();
+		Machine::write_memory(&mut m, 2, 6, (43 << 8) + 150);
+		assert_eq!(43, m.main_memory[6]);
+		assert_eq!(150, m.main_memory[7]);
+	}
 }