diff --git a/src/processor/memory/mmio/joypad.rs b/src/processor/memory/mmio/joypad.rs
index 1dd2b04..f46ae61 100644
--- a/src/processor/memory/mmio/joypad.rs
+++ b/src/processor/memory/mmio/joypad.rs
@@ -114,7 +114,7 @@ impl Default for Joypad {
     fn default() -> Self {
         Self {
             sel_action: true,
-            sel_direction: false,
+            sel_direction: true,
             down: false,
             up: false,
             left: false,
diff --git a/src/processor/memory/mmio/serial.rs b/src/processor/memory/mmio/serial.rs
index e6daf0f..94d807b 100644
--- a/src/processor/memory/mmio/serial.rs
+++ b/src/processor/memory/mmio/serial.rs
@@ -25,7 +25,7 @@ impl Default for SerialControl {
         Self {
             transfer_in_progress: false,
             clock_speed: ClockSpeed::Normal,
-            clock_source: ClockSource::Internal,
+            clock_source: ClockSource::External,
         }
     }
 }
@@ -103,7 +103,7 @@ impl Serial {
 impl Default for Serial {
     fn default() -> Self {
         Self {
-            byte: 0xFF,
+            byte: 0,
             output_byte: 0,
             bits_remaining: 7,
             control: SerialControl::default(),