Rename to DuckStation

src/core/memory_card.h

@@ -0,0 +1,80 @@
+#pragma once
+#include "common/bitfield.h"
+#include "pad_device.h"
+#include <memory>
+#include <array>
+
+class MemoryCard final : public PadDevice
+{
+public:
+  enum : u32
+  {
+    DATA_SIZE = 128 * 1024, // 1mbit
+    SECTOR_SIZE = 128,
+    NUM_SECTORS = DATA_SIZE / SECTOR_SIZE
+  };
+
+  MemoryCard();
+  ~MemoryCard() override;
+
+  static std::shared_ptr<MemoryCard> Create();
+
+  void Reset() override;
+  bool DoState(StateWrapper& sw) override;
+
+  void ResetTransferState() override;
+  bool Transfer(const u8 data_in, u8* data_out) override;
+
+  void Format();
+
+private:
+  union FLAG
+  {
+    u8 bits;
+
+    BitField<u8, bool, 3, 1> no_write_yet;
+    BitField<u8, bool, 2, 1> write_error;
+  };
+
+  FLAG m_FLAG = {};
+
+  enum class State : u8
+  {
+    Idle,
+    Command,
+
+    ReadCardID1,
+    ReadCardID2,
+    ReadAddressMSB,
+    ReadAddressLSB,
+    ReadACK1,
+    ReadACK2,
+    ReadConfirmAddressMSB,
+    ReadConfirmAddressLSB,
+    ReadData,
+    ReadChecksum,
+    ReadEnd,
+
+    WriteCardID1,
+    WriteCardID2,
+    WriteAddressMSB,
+    WriteAddressLSB,
+    WriteData,
+    WriteChecksum,
+    WriteACK1,
+    WriteACK2,
+    WriteEnd,
+  };
+
+  static u8 ChecksumFrame(const u8* fptr);
+
+  u8* GetSectorPtr(u32 sector);
+
+  State m_state = State::Idle;
+  u16 m_address = 0;
+  u8 m_sector_offset = 0;
+  u8 m_checksum = 0;
+  u8 m_last_byte = 0;
+
+  std::array<u8, DATA_SIZE> m_data{};
+};