diff --git a/Source/Core/Core/CMakeLists.txt b/Source/Core/Core/CMakeLists.txt
index b4437747e8..09b69a620e 100644
--- a/Source/Core/Core/CMakeLists.txt
+++ b/Source/Core/Core/CMakeLists.txt
@@ -203,6 +203,8 @@ add_library(core
   HW/EXI/EXI_DeviceAD16.h
   HW/EXI/EXI_DeviceAGP.cpp
   HW/EXI/EXI_DeviceAGP.h
+  HW/EXI/EXI_DeviceBaseboard.cpp
+  HW/EXI/EXI_DeviceBaseboard.h
   HW/EXI/EXI_DeviceDummy.cpp
   HW/EXI/EXI_DeviceDummy.h
   HW/EXI/EXI_DeviceEthernet.cpp
diff --git a/Source/Core/Core/ConfigManager.cpp b/Source/Core/Core/ConfigManager.cpp
index a480c7622d..e005e78341 100644
--- a/Source/Core/Core/ConfigManager.cpp
+++ b/Source/Core/Core/ConfigManager.cpp
@@ -307,6 +307,7 @@ void SConfig::LoadDefaults()
 
   auto& system = Core::System::GetInstance();
   system.SetIsWii(false);
+  system.SetIsTriforce(false);
 
   ResetRunningGameMetadata();
 }
@@ -330,6 +331,7 @@ struct SetGameMetadata
   {
     *region = disc.volume->GetRegion();
     system.SetIsWii(disc.volume->GetVolumeType() == DiscIO::Platform::WiiDisc);
+    system.SetIsTriforce(disc.volume->GetVolumeType() == DiscIO::Platform::Triforce);
     config->m_disc_booted_from_game_list = true;
     config->SetRunningGameMetadata(*disc.volume, disc.volume->GetGamePartition());
     return true;
diff --git a/Source/Core/Core/HW/EXI/EXI.cpp b/Source/Core/Core/HW/EXI/EXI.cpp
index 303191c574..d676dc4845 100644
--- a/Source/Core/Core/HW/EXI/EXI.cpp
+++ b/Source/Core/Core/HW/EXI/EXI.cpp
@@ -66,6 +66,18 @@ void ExpansionInterfaceManager::AddMemoryCard(Slot slot)
   m_channels[SlotToEXIChannel(slot)]->AddDevice(memorycard_device, SlotToEXIDevice(slot));
 }
 
+void ExpansionInterfaceManager::AddSP1Device()
+{
+  EXIDeviceType sp1_device = EXIDeviceType::Baseboard;
+  auto& system = Core::System::GetInstance();
+  if (system.IsTriforce())
+  {
+    sp1_device = Config::Get(Config::MAIN_SERIAL_PORT_1);
+  }
+
+  m_channels[0]->AddDevice(sp1_device, SlotToEXIDevice(Slot::SP1));
+}
+
 u8 SlotToEXIChannel(Slot slot)
 {
   switch (slot)
@@ -145,6 +157,7 @@ void ExpansionInterfaceManager::Init(const Sram* override_sram)
     AddMemoryCard(slot);
 
   m_channels[0]->AddDevice(EXIDeviceType::MaskROM, 1);
+  AddSP1Device();
   m_channels[SlotToEXIChannel(Slot::SP1)]->AddDevice(Config::Get(Config::MAIN_SERIAL_PORT_1),
                                                      SlotToEXIDevice(Slot::SP1));
   m_channels[SlotToEXIChannel(Slot::SP2)]->AddDevice(Config::Get(Config::MAIN_SERIAL_PORT_2),
diff --git a/Source/Core/Core/HW/EXI/EXI.h b/Source/Core/Core/HW/EXI/EXI.h
index 7ded905b98..f0ea5fbfb5 100644
--- a/Source/Core/Core/HW/EXI/EXI.h
+++ b/Source/Core/Core/HW/EXI/EXI.h
@@ -89,6 +89,7 @@ public:
 
 private:
   void AddMemoryCard(Slot slot);
+  void AddSP1Device();
 
   static void ChangeDeviceCallback(Core::System& system, u64 userdata, s64 cycles_late);
   static void UpdateInterruptsCallback(Core::System& system, u64 userdata, s64 cycles_late);
diff --git a/Source/Core/Core/HW/EXI/EXI_Device.cpp b/Source/Core/Core/HW/EXI/EXI_Device.cpp
index 6c416d5387..ac92c7b723 100644
--- a/Source/Core/Core/HW/EXI/EXI_Device.cpp
+++ b/Source/Core/Core/HW/EXI/EXI_Device.cpp
@@ -9,6 +9,7 @@
 #include "Common/MsgHandler.h"
 #include "Core/HW/EXI/EXI_DeviceAD16.h"
 #include "Core/HW/EXI/EXI_DeviceAGP.h"
+#include "Core/HW/EXI/EXI_DeviceBaseboard.h"
 #include "Core/HW/EXI/EXI_DeviceDummy.h"
 #include "Core/HW/EXI/EXI_DeviceEthernet.h"
 #include "Core/HW/EXI/EXI_DeviceGecko.h"
@@ -171,7 +172,10 @@ std::unique_ptr<IEXIDevice> EXIDevice_Create(Core::System& system, const EXIDevi
     result = std::make_unique<CEXIAgp>(system, slot);
     break;
 
-  case EXIDeviceType::AMBaseboard:
+  case EXIDeviceType::Baseboard:
+    result = std::make_unique<CEXIBaseboard>(system);
+    break;
+
   case EXIDeviceType::None:
   default:
     result = std::make_unique<IEXIDevice>(system);
diff --git a/Source/Core/Core/HW/EXI/EXI_Device.h b/Source/Core/Core/HW/EXI/EXI_Device.h
index db74306df0..25263af425 100644
--- a/Source/Core/Core/HW/EXI/EXI_Device.h
+++ b/Source/Core/Core/HW/EXI/EXI_Device.h
@@ -30,9 +30,7 @@ enum class EXIDeviceType : int
   AD16,
   Microphone,
   Ethernet,
-  // Was used for Triforce in the past, but the implementation is no longer in Dolphin.
-  // It's kept here so that values below will stay constant.
-  AMBaseboard,
+  Baseboard,
   Gecko,
   // Only used when creating a device by EXIDevice_Create.
   // Converted to MemoryCard internally.
@@ -98,7 +96,7 @@ struct fmt::formatter<ExpansionInterface::EXIDeviceType>
       _trans("AD16"),
       _trans("Microphone"),
       _trans("Broadband Adapter (TAP)"),
-      _trans("Triforce AM Baseboard"),
+      _trans("Triforce Baseboard"),
       _trans("USB Gecko"),
       _trans("GCI Folder"),
       _trans("Advance Game Port"),
diff --git a/Source/Core/Core/HW/EXI/EXI_DeviceBaseboard.cpp b/Source/Core/Core/HW/EXI/EXI_DeviceBaseboard.cpp
new file mode 100644
index 0000000000..a9200ac85a
--- /dev/null
+++ b/Source/Core/Core/HW/EXI/EXI_DeviceBaseboard.cpp
@@ -0,0 +1,57 @@
+// Copyright 2013 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "Core/HW/EXI/EXI_DeviceBaseboard.h"
+
+#include "Common/Assert.h"
+#include "Common/ChunkFile.h"
+#include "Common/CommonTypes.h"
+#include "Common/Logging/Log.h"
+
+namespace ExpansionInterface
+{
+CEXIBaseboard::CEXIBaseboard(Core::System& system) : IEXIDevice(system)
+{
+}
+
+void CEXIBaseboard::SetCS(int cs)
+{
+  if (cs)
+    m_position = 0;
+}
+
+bool CEXIBaseboard::IsPresent() const
+{
+  return true;
+}
+
+void CEXIBaseboard::TransferByte(u8& byte)
+{
+  if (m_position == 0)
+  {
+    m_command = byte;
+  }
+  else
+  {
+    switch (m_command)
+    {
+    case 0x00:
+    {
+      static constexpr std::array<u8, 4> ID = {0x06, 0x04, 0x10, 0x00};
+      byte = ID[(m_position - 2) & 3];
+      break;
+    }
+    default:
+      ERROR_LOG_FMT(EXPANSIONINTERFACE, "EXI BASEBOARD: Unhandled command {:#x} {:#x}", m_command,
+                    m_position);
+    }
+  }
+  m_position++;
+}
+
+void CEXIBaseboard::DoState(PointerWrap& p)
+{
+  p.Do(m_position);
+  p.Do(m_command);
+}
+}  // namespace ExpansionInterface
diff --git a/Source/Core/Core/HW/EXI/EXI_DeviceBaseboard.h b/Source/Core/Core/HW/EXI/EXI_DeviceBaseboard.h
new file mode 100644
index 0000000000..4c534428c9
--- /dev/null
+++ b/Source/Core/Core/HW/EXI/EXI_DeviceBaseboard.h
@@ -0,0 +1,27 @@
+// Copyright 2013 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "Core/HW/EXI/EXI_Device.h"
+
+class PointerWrap;
+
+namespace ExpansionInterface
+{
+class CEXIBaseboard : public IEXIDevice
+{
+public:
+  CEXIBaseboard(Core::System& system);
+  void SetCS(int cs) override;
+  bool IsPresent() const override;
+  void DoState(PointerWrap& p) override;
+
+private:
+  // STATE_TO_SAVE
+  u32 m_position = 0;
+  u32 m_command = 0;
+
+  void TransferByte(u8& byte) override;
+};
+}  // namespace ExpansionInterface
diff --git a/Source/Core/Core/State.cpp b/Source/Core/Core/State.cpp
index 44465b3f42..9620cfccd4 100644
--- a/Source/Core/Core/State.cpp
+++ b/Source/Core/Core/State.cpp
@@ -99,7 +99,7 @@ static size_t s_state_writes_in_queue;
 static std::condition_variable s_state_write_queue_is_empty;
 
 // Don't forget to increase this after doing changes on the savestate system
-constexpr u32 STATE_VERSION = 172;  // Last changed in PR 13385
+constexpr u32 STATE_VERSION = 173;  // Last changed in PR 10084
 
 // Increase this if the StateExtendedHeader definition changes
 constexpr u32 EXTENDED_HEADER_VERSION = 1;  // Last changed in PR 12217
diff --git a/Source/Core/Core/System.h b/Source/Core/Core/System.h
index 9ec8391ff0..0ab86e658d 100644
--- a/Source/Core/Core/System.h
+++ b/Source/Core/Core/System.h
@@ -141,10 +141,12 @@ public:
   bool IsMMUMode() const { return m_mmu_enabled; }
   bool IsPauseOnPanicMode() const { return m_pause_on_panic_enabled; }
   bool IsMIOS() const { return m_is_mios; }
+  bool IsTriforce() const { return m_is_triforce; }
   bool IsWii() const { return m_is_wii; }
   bool IsBranchWatchIgnoreApploader() { return m_branch_watch_ignore_apploader; }
 
   void SetIsMIOS(bool is_mios) { m_is_mios = is_mios; }
+  void SetIsTriforce(bool is_triforce) { m_is_triforce = is_triforce; }
   void SetIsWii(bool is_wii) { m_is_wii = is_wii; }
   void SetIsBranchWatchIgnoreApploader(bool enable) { m_branch_watch_ignore_apploader = enable; }
 
@@ -205,6 +207,7 @@ private:
   bool m_mmu_enabled = false;
   bool m_pause_on_panic_enabled = false;
   bool m_is_mios = false;
+  bool m_is_triforce = false;
   bool m_is_wii = false;
   bool m_branch_watch_ignore_apploader = false;
 };
diff --git a/Source/Core/DolphinLib.props b/Source/Core/DolphinLib.props
index 388367afd1..4c7764202d 100644
--- a/Source/Core/DolphinLib.props
+++ b/Source/Core/DolphinLib.props
@@ -281,6 +281,7 @@
     <ClInclude Include="Core\HW\EXI\EXI_Device.h" />
     <ClInclude Include="Core\HW\EXI\EXI_DeviceAD16.h" />
     <ClInclude Include="Core\HW\EXI\EXI_DeviceAGP.h" />
+    <ClInclude Include="Core\HW\EXI\EXI_DeviceBaseboard.h" />
     <ClInclude Include="Core\HW\EXI\EXI_DeviceDummy.h" />
     <ClInclude Include="Core\HW\EXI\EXI_DeviceEthernet.h" />
     <ClInclude Include="Core\HW\EXI\EXI_DeviceGecko.h" />
@@ -948,6 +949,7 @@
     <ClCompile Include="Core\HW\EXI\EXI_Device.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI_DeviceAD16.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI_DeviceAGP.cpp" />
+    <ClCompile Include="Core\HW\EXI\EXI_DeviceBaseboard.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI_DeviceDummy.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI_DeviceEthernet.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI_DeviceGecko.cpp" />