diff --git a/Source/Core/Core/HW/SI/SI_Device.cpp b/Source/Core/Core/HW/SI/SI_Device.cpp
index 8ea3e75d02..451523624b 100644
--- a/Source/Core/Core/HW/SI/SI_Device.cpp
+++ b/Source/Core/Core/HW/SI/SI_Device.cpp
@@ -11,6 +11,7 @@
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
 #include "Common/MsgHandler.h"
+#include "Common/Swap.h"
 #include "Core/HW/SI/SI_DeviceDanceMat.h"
 #include "Core/HW/SI/SI_DeviceGBA.h"
 #ifdef HAS_LIBMGBA
@@ -87,6 +88,15 @@ void ISIDevice::OnEvent(u64 userdata, s64 cycles_late)
 {
 }
 
+int ISIDevice::CreateStatusResponse(u32 si_device_id, u8* buffer)
+{
+  constexpr int RESPONSE_LENGTH = 3;
+
+  Common::BigEndianValue<u32> id(si_device_id);
+  std::memcpy(buffer, &id, RESPONSE_LENGTH);
+  return RESPONSE_LENGTH;
+}
+
 int SIDevice_GetGBATransferTime(const SystemTimers::SystemTimersManager& timers,
                                 EBufferCommands cmd)
 {
diff --git a/Source/Core/Core/HW/SI/SI_Device.h b/Source/Core/Core/HW/SI/SI_Device.h
index ebab7e3235..234c475e5f 100644
--- a/Source/Core/Core/HW/SI/SI_Device.h
+++ b/Source/Core/Core/HW/SI/SI_Device.h
@@ -123,7 +123,12 @@ public:
   SIDevices GetDeviceType() const;
 
   // Run the SI Buffer
+  // Return value:
+  //  positive: The response length.
+  //  0: Response not ready, we will try again `TransferInterval()` cycles later.
+  //  -1: No response.
   virtual int RunBuffer(u8* buffer, int request_length);
+
   virtual int TransferInterval();
 
   virtual DataResponse GetData(u32& hi, u32& low) = 0;
@@ -138,6 +143,9 @@ public:
   virtual void OnEvent(u64 userdata, s64 cycles_late);
 
 protected:
+  // Only the three high bytes of `si_device_id` are used.
+  static int CreateStatusResponse(u32 si_device_id, u8* buffer);
+
   Core::System& m_system;
 
   int m_device_number;
diff --git a/Source/Core/Core/HW/SI/SI_DeviceDanceMat.cpp b/Source/Core/Core/HW/SI/SI_DeviceDanceMat.cpp
index d7ca1c8a3a..5d97dbd684 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceDanceMat.cpp
+++ b/Source/Core/Core/HW/SI/SI_DeviceDanceMat.cpp
@@ -3,10 +3,7 @@
 
 #include "Core/HW/SI/SI_DeviceDanceMat.h"
 
-#include <cstring>
-
 #include "Common/CommonTypes.h"
-#include "Common/Swap.h"
 #include "InputCommon/GCPadStatus.h"
 
 namespace SerialInterface
@@ -22,11 +19,7 @@ int CSIDevice_DanceMat::RunBuffer(u8* buffer, int request_length)
   const auto command = static_cast<EBufferCommands>(buffer[0]);
   if (command == EBufferCommands::CMD_STATUS)
   {
-    ISIDevice::RunBuffer(buffer, request_length);
-
-    const u32 id = Common::swap32(SI_DANCEMAT);
-    std::memcpy(buffer, &id, sizeof(id));
-    return sizeof(id);
+    return CreateStatusResponse(SI_DANCEMAT, buffer);
   }
   return CSIDevice_GCController::RunBuffer(buffer, request_length);
 }
diff --git a/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp b/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp
index b9c22f1d58..eb7c06343d 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp
+++ b/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp
@@ -10,7 +10,6 @@
 #include "Common/ChunkFile.h"
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
-#include "Common/Swap.h"
 #include "Core/Core.h"
 #include "Core/CoreTiming.h"
 #include "Core/HW/GBACore.h"
diff --git a/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp b/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp
index beb633f499..270e75f56a 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp
+++ b/Source/Core/Core/HW/SI/SI_DeviceGCController.cpp
@@ -57,9 +57,7 @@ int CSIDevice_GCController::RunBuffer(u8* buffer, int request_length)
   case EBufferCommands::CMD_STATUS:
   case EBufferCommands::CMD_RESET:
   {
-    const u32 id = Common::swap32(SI_GC_CONTROLLER);
-    std::memcpy(buffer, &id, sizeof(id));
-    return sizeof(id);
+    return CreateStatusResponse(SI_GC_CONTROLLER, buffer);
   }
 
   case EBufferCommands::CMD_DIRECT:
diff --git a/Source/Core/Core/HW/SI/SI_DeviceGCSteeringWheel.cpp b/Source/Core/Core/HW/SI/SI_DeviceGCSteeringWheel.cpp
index cb639f415e..a3ca7e9ebe 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceGCSteeringWheel.cpp
+++ b/Source/Core/Core/HW/SI/SI_DeviceGCSteeringWheel.cpp
@@ -34,9 +34,7 @@ int CSIDevice_GCSteeringWheel::RunBuffer(u8* buffer, int request_length)
   case EBufferCommands::CMD_STATUS:
   case EBufferCommands::CMD_RESET:
   {
-    const u32 id = Common::swap32(SI_GC_STEERING);
-    std::memcpy(buffer, &id, sizeof(id));
-    return sizeof(id);
+    return CreateStatusResponse(SI_GC_STEERING, buffer);
   }
   default:
     return CSIDevice_GCController::RunBuffer(buffer, request_length);
diff --git a/Source/Core/Core/HW/SI/SI_DeviceKeyboard.cpp b/Source/Core/Core/HW/SI/SI_DeviceKeyboard.cpp
index 28ffc13f61..e3655bc904 100644
--- a/Source/Core/Core/HW/SI/SI_DeviceKeyboard.cpp
+++ b/Source/Core/Core/HW/SI/SI_DeviceKeyboard.cpp
@@ -9,7 +9,6 @@
 #include "Common/ChunkFile.h"
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
-#include "Common/Swap.h"
 #include "Core/HW/GCKeyboard.h"
 #include "InputCommon/KeyboardStatus.h"
 
@@ -35,9 +34,7 @@ int CSIDevice_Keyboard::RunBuffer(u8* buffer, int request_length)
   case EBufferCommands::CMD_STATUS:
   case EBufferCommands::CMD_RESET:
   {
-    const u32 id = Common::swap32(SI_GC_KEYBOARD);
-    std::memcpy(buffer, &id, sizeof(id));
-    return sizeof(id);
+    return CreateStatusResponse(SI_GC_KEYBOARD, buffer);
   }
 
   case EBufferCommands::CMD_DIRECT_KB: