1 files changed, 67 insertions, 2 deletions

diff --git a/vdp.hpp b/vdp.hpp
index 0e911c9..cd93938 100644
--- a/vdp.hpp
+++ b/vdp.hpp
@@ -5,19 +5,84 @@
 
 #include "bus.hpp"
 
-#include <cstdio>
+#include <cstddef>
+#include <cstring>
 
 class VDP {
     public:
         VDP(const uint32_t base_address_a = VDP_START): base_address(base_address_a) {}
         uint32_t Read(uint32_t offset, enum bitness);
         void Write(uint32_t offset, enum bitness, uint32_t value);
+        void Reset();
 
         const uint32_t base_address;
 
     private:
+        struct StatusRegister {
+            bool fifo_not_empty{};
+            bool fifo_full{};
+            bool v_irq{};
+            bool sprites_overflow{};
+            bool sprites_collision{};
+            bool odd_frame{};
+            bool vblank{};
+            bool hblank{};
+            bool dma_busy{};
+            bool pal_mode{};
+        };
+
+        enum class AddressMode: uint8_t {
+            kVRAMWrite = 1,
+            kCRAMWrite = 3,
+            kVSRAMWrite = 5,
+            kVRAMRead = 0,
+            kCRAMRead = 8,
+            kVSRAMRead = 4,
+        };
+
+        enum class RegID: size_t {
+            kModeSet1 = 0,
+            kModeSet2 = 1,
+            kScrollAAddress = 2,
+            kWindowAddress = 3,
+            kScrollBAddress = 4,
+            kSpritesTableAddress = 5,
+            kBackgroundColor = 7,
+            kHint = 10,
+            kModeSet3 = 11,
+            kModeSet4 = 12,
+            kHScrollTableAddress = 13,
+            kAutoIncrement = 15,
+            kScrollSize = 16,
+            kWindowHorizontalPosition = 17,
+            kWindowVertialPosition = 18,
+            kDMACounterLow = 19,
+            kDMACounterHigh = 20,
+            kDMASourceAddressLow = 21,
+            kDMASourceAddressMid = 22,
+            kDMASourceAddressHigh = 23,
+            kRegistersCount, ///< Keep it last
+        };
+
+        void writeData(uint8_t address_mode, uint16_t address, uint16_t value);
         void writeControl(uint16_t value);
+        uint16_t readData(uint8_t address_mode, uint16_t address);
+        uint16_t readStatusRegister() const;
+
+        const char* addressModeToString(uint8_t address_mode);
+        const char* regIDToString(RegID);
+
+        static constexpr size_t kRegistersCount = static_cast<size_t>(RegID::kRegistersCount);
+        static constexpr size_t kVRAMSize = 64*1024;
+        static constexpr size_t kCRAMSize = 64*2;
+        static constexpr size_t kVSRAMSize = 40*2;
 
-        static constexpr size_t kRegistersCount = 0x18;
+        StatusRegister _status{};
+        bool _control_write_second_word{};
+        uint8_t _address_mode{};
+        uint16_t _address{};
         uint8_t _reg[kRegistersCount]{};
+        uint8_t _vram[kVRAMSize]{};
+        uint8_t _cram[kCRAMSize]{};
+        uint8_t _vsram[kVSRAMSize]{};
 };