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GliniakGliniak
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[R22] Many Changes, More Below:
- Implemented DMA controller - Implemented CPU Cycles/Ticks - Switched Video Stuff from DMA to Video Controller - Fixed Crash during program shutdown - Added Table for Opcodes Ticks
1 parent aa95167 commit 58e07ba

11 files changed

+412
-180
lines changed

‎README.md

+8-4
Original file line numberDiff line numberDiff line change
@@ -3,8 +3,8 @@ Not working (YET) Gameboy (Classic) Emulator written in C#. Please do not post t
33
This is just a learning project. Thank you kindly.
44

55
Progress:
6-
- CPU: 40%
7-
- GPU: 5%
6+
- CPU: 60%
7+
- GPU: 40%
88
- Memory: 90%
99
- Cartridge: 50%
1010
- Sound: 0%
@@ -18,11 +18,15 @@ CPU:
1818
- IRQ Support
1919
- (Probably) Some fixes to actually implemented one
2020

21+
LONG TERM:
22+
- Recompiler
23+
2124
GPU:
22-
- Everything, Only Basic OpenGL window is working ATM
25+
- Fix background rendering, Add Sprites rendering.
2326

2427
Memory:
25-
- Basic functionality is working, need to add MCB support and come assertions to r/w memory operations
28+
- Basic functionality is working, need to add MCB support and some assertions to r/w memory operations
29+
- Check if DMA works good
2630

2731
Cartridge:
2832
- MBC Support

‎SharpBoy/Emulator/CPU/DMAController.cs

+16-115
Original file line numberDiff line numberDiff line change
@@ -7,45 +7,6 @@
77

88
namespace SharpBoy
99
{
10-
// 40x32bits OAMobj
11-
class Sprite
12-
{
13-
Byte posX;
14-
Byte posY;
15-
Byte tile;
16-
Byte Flags; // Bits 4 to 7
17-
18-
public Sprite(Byte[] data, Byte length)
19-
{
20-
if (length != 4)
21-
{
22-
// Wrong Sprite data?
23-
return;
24-
}
25-
26-
posX = data[0];
27-
posY = data[1];
28-
tile = data[2];
29-
Flags = data[3];
30-
}
31-
}
32-
33-
public enum GameboyColors
34-
{
35-
GB_COLOR_WHITE,
36-
GB_COLOR_LIGHT_GREY,
37-
GB_COLOR_DARK_GREY,
38-
GB_COLOR_BLACK
39-
};
40-
41-
public enum LCDmodeFlag
42-
{
43-
LCD_MODE_FLAG_H_BLANK,
44-
LCD_MODE_FLAG_V_BLANK,
45-
LCD_MODE_FLAG_OAM_READ, // OAM Read time, moment when cpu dont have access to OAM
46-
LCD_MODE_FLAG_DATA_TO_LCD // During data send to renderer (LCD Driver)
47-
};
48-
4910
// AKA LCD CONTROLLER (In CGB)
5011

5112
/*
@@ -57,94 +18,34 @@ public enum LCDmodeFlag
5718

5819
class DMAController
5920
{
60-
public DMAController() { }
21+
private Boolean enabled = false;
22+
private UInt16 adrBegin = 0;
23+
private UInt16 bytesCopied = 0;
6124

62-
// OAM mem is available only during mode 0-1 (H and Vblank period), However DMA have access to it all time (0xFF46)
63-
public Byte[] GetOAM() { return Program.emulator.GetMemory().ReadFromMemory(0xFE00, 0x009F); }
64-
65-
// Nah not actually that good i guess
66-
public Byte GetLCDCregister() { return Program.emulator.GetMemory().ReadFromMemory(0xFF40); }
67-
public BitArray GetLCDCregisterBits() { return new BitArray(GetLCDCregister()); }
68-
69-
// TODO: Bit 7 Check!
70-
public void SetLCDCregister(Byte value) { Program.emulator.GetMemory().WriteToMemory(0xFF40, value); }
71-
public void SetLCDCregisterBit(Byte bit, bool toogle)
72-
{
73-
// Fix this!
74-
SetLCDCregister(toogle ? (Byte)(GetLCDCregister() | (1 << bit)) : (Byte)(GetLCDCregister() ^ (1 << bit)));
75-
}
76-
77-
public bool IsDisplayOn() { return GetLCDCregisterBits().Get(7); }
78-
79-
/*
80-
Bit 6 - LYC=LY Coincidence Interrupt (1=Enable) (Read/Write)
81-
Bit 5 - Mode 2 OAM Interrupt (1=Enable) (Read/Write)
82-
Bit 4 - Mode 1 V-Blank Interrupt (1=Enable) (Read/Write)
83-
Bit 3 - Mode 0 H-Blank Interrupt (1=Enable) (Read/Write)
84-
Bit 2 - Coincidence Flag (0:LYC<>LY, 1:LYC=LY) (Read Only)
85-
Bit 1-0 - Mode Flag (Mode 0-3, see below) (Read Only)
86-
0: During H-Blank
87-
1: During V-Blank
88-
2: During Searching OAM
89-
3: During Transferring Data to LCD Driver
90-
*/
25+
public DMAController() { }
9126

92-
public Byte GetSTATregister() { return Program.emulator.GetMemory().ReadFromMemory(0xFF41); }
93-
public BitArray GetSTATregisterBits() { return new BitArray(GetSTATregister()); }
27+
public Byte GetDMA() { return Program.emulator.GetMemory().ReadFromMemory(0xFF46); }
9428

95-
public void setSTATregister(Byte value) { Program.emulator.GetMemory().WriteToMemory(0xFF41, value); }
96-
public void setSTATregisterBit(Byte bit, bool toogle)
29+
public void StartOAM(UInt16 adr)
9730
{
98-
// Fix this!
99-
setSTATregister(toogle ? (Byte)(GetSTATregister() | (1 << bit)) : (Byte)(GetSTATregister() ^ (1 << bit)));
31+
enabled = true;
32+
adrBegin = (UInt16)(adr << 8); // 0x0100
33+
bytesCopied = 0;
10034
}
10135

102-
public LCDmodeFlag getSTATmodeFlag() { return (LCDmodeFlag)(GetSTATregister() & 0x03); }
103-
104-
public Byte GetSCY() { return Program.emulator.GetMemory().ReadFromMemory(0xFF42); }
105-
public Byte GetSCX() { return Program.emulator.GetMemory().ReadFromMemory(0xFF43); }
106-
107-
public void SetSCY(Byte value) { Program.emulator.GetMemory().WriteToMemory(0xFF42, value); }
108-
public void SetSCX(Byte value) { Program.emulator.GetMemory().WriteToMemory(0xFF43, value); }
109-
110-
public Byte GetLY() { return Program.emulator.GetMemory().ReadFromMemory(0xFF44); }
111-
public void SetLY(Byte value)
36+
public void Tick()
11237
{
113-
if(value > 153)
114-
{
115-
Program.emulator.GetMemory().WriteToMemory(0xFF44, 0);
116-
return;
117-
}
118-
// Vblank period
119-
if(value > 143 && !Program.emulator.getCPU().GetInterruptController().IsInQueue(InterruptController.Interrupt.INTERRUPT_VBLANK))
120-
{
121-
// Raise Interrupt!
122-
Program.emulator.getCPU().GetInterruptController().RaiseInterrupt(InterruptController.Interrupt.INTERRUPT_VBLANK);
123-
//Program.emulator.GetMemory().WriteToMemory(0xFF44, 0);
38+
if (!enabled)
12439
return;
125-
}
126-
127-
128-
Program.emulator.GetMemory().WriteToMemory(0xFF44, value);
129-
}
130-
131-
public Byte GetLYC() { return Program.emulator.GetMemory().ReadFromMemory(0xFF45); }
13240

133-
public bool CompareLYtoLYC() { return GetLY() == GetLYC(); }
134-
135-
public void Update()
136-
{
137-
if(CompareLYtoLYC())
41+
// It always copies 160 (0xA0) bytes of data
42+
while(bytesCopied < 160)
13843
{
139-
// STAT INTERRUPT
140-
Program.emulator.getCPU().GetInterruptController().RaiseInterrupt(InterruptController.Interrupt.INTERRUPT_LCDC);
141-
44+
Program.emulator.GetMemory().WriteToMemory((UInt16)(0xFE00 + bytesCopied), Program.emulator.GetMemory().ReadFromMemory((UInt16)(adrBegin + bytesCopied)));
45+
bytesCopied++;
14246
}
143-
// Draw next line
144-
SetLY((Byte)(GetLY() + 1));
145-
14647

147-
//Logger.AppendLog(Logger.LOG_LEVEL.LOG_LEVEL_DEBUG, "DMAController: Update()");
48+
enabled = false;
14849
}
14950
}
15051
}

‎SharpBoy/Emulator/CPU/InterruptController.cs

+1-1
Original file line numberDiff line numberDiff line change
@@ -33,7 +33,7 @@ public Interrupt Update()
3333

3434
public void RaiseInterrupt(Interrupt interrupt)
3535
{
36-
//Logger.AppendLog(Logger.LOG_LEVEL.LOG_LEVEL_WARNING, "InterruptController: RaiseInterrupt(" + interrupt.ToString() + ")");
36+
Logger.AppendLog(Logger.LOG_LEVEL.LOG_LEVEL_WARNING, "InterruptController: RaiseInterrupt(" + interrupt.ToString() + ")");
3737

3838
switch(interrupt)
3939
{

‎SharpBoy/Emulator/CPU/Opcodes.cs

+6
Original file line numberDiff line numberDiff line change
@@ -140,6 +140,12 @@ public enum Opcode : Byte
140140

141141
}
142142

143+
static public Dictionary<Opcode, Byte> opcodeTimings = new Dictionary<Opcode, byte>()
144+
{
145+
{ Opcode.OPCODE_ADD_A_A, 1 },
146+
147+
};
148+
143149
static Dictionary<Opcode, Action> opcodes = new Dictionary<Opcode, Action>()
144150
{
145151
{ Opcode.OPCODE_NOP, () => nop_instruction() },

‎SharpBoy/Emulator/CPU/cpu.cs

+36-39
Original file line numberDiff line numberDiff line change
@@ -43,16 +43,13 @@ public enum Flag_Register_Bits : Byte
4343

4444
public Task cpuTask;
4545

46-
// FOR FUTURE USAGE
47-
private readonly double CPU_CLOCK = 1/(4.194304 * 1000000);
48-
private double CPU_CLOCK_MULTIPLY = 10.0;
49-
private Boolean FAST_CLOCK = true;
50-
5146
private InterruptController irController = new InterruptController();
5247
private InternalTimer internalTimer = new InternalTimer();
5348
private DMAController dmaController = new DMAController();
49+
private VideoController videoController = new VideoController();
5450

5551
public InterruptController GetInterruptController() { return irController; }
52+
public DMAController GetDMAController() { return dmaController; }
5653

5754
public CPU() { }
5855

@@ -195,9 +192,10 @@ public void StackPop(ref UInt16 value)
195192
value = ((UInt16)((hi << 8) | lo));
196193
}
197194

198-
public void exe_ins()
195+
public Byte exe_ins()
199196
{
200-
Byte op = Program.emulator.GetMemory().ReadFromMemory(reg_pc);
197+
Byte opTime = 1;
198+
Opcodes.Opcode op = (Opcodes.Opcode)(Program.emulator.GetMemory().ReadFromMemory(reg_pc));
201199

202200
// Logger.AppendLog(Logger.LOG_LEVEL.LOG_LEVEL_DEBUG, "[" + String.Format("{0:X4}", get_reg_pc()) + "]: " + String.Format("{0:X2}", op) + "PRE Execute");
203201
if (!Enum.IsDefined(typeof(Opcodes.Opcode), op))
@@ -206,22 +204,24 @@ public void exe_ins()
206204
+ " At Address: " + String.Format("{0:X4}", reg_pc));
207205

208206
set_reg_pc((UInt16)(get_reg_pc() + 1));
209-
return;
207+
return opTime;
210208
}
211209

212210
// Special Execute for CB Opcodes
213-
if((Opcodes.Opcode)op == Opcodes.Opcode.OPCODE_INTERNAL_CB)
211+
if(op == Opcodes.Opcode.OPCODE_INTERNAL_CB)
214212
{
215213
// Increase Program Counter to next location
216214
set_reg_pc((UInt16)(get_reg_pc() + 1));
217-
op = Program.emulator.GetMemory().ReadFromMemory(reg_pc);
218-
219-
OpcodesCB.ExecuteOpcodeCB((OpcodesCB.OpcodeCB)op);
220-
return;
215+
OpcodesCB.ExecuteOpcodeCB((OpcodesCB.OpcodeCB)(Program.emulator.GetMemory().ReadFromMemory(reg_pc)));
216+
// TODO: IMplement Clocks for CB Opcodes
217+
return opTime;
221218
}
222219

223-
Logger.AppendLog(Logger.LOG_LEVEL.LOG_LEVEL_DEBUG, "[" + String.Format("{0:X4}", get_reg_pc()) + "]: " + ((Opcodes.Opcode)op).ToString() + " Executing");
224-
Opcodes.ExecuteOpcode((Opcodes.Opcode)op);
220+
Logger.AppendLog(Logger.LOG_LEVEL.LOG_LEVEL_DEBUG, "[" + String.Format("{0:X4}", get_reg_pc()) + "]: " + op.ToString() + " Executing");
221+
Opcodes.ExecuteOpcode(op);
222+
opTime = Opcodes.opcodeTimings.ContainsKey(op) ? Opcodes.opcodeTimings[op] : (byte)1;
223+
224+
return opTime;
225225
}
226226

227227
public void Reset(bool BiosLoaded = false)
@@ -249,43 +249,40 @@ public void Reset(bool BiosLoaded = false)
249249

250250
public void ExeCycle()
251251
{
252+
Byte ticks = exe_ins();
253+
252254
irController.Update();
253255
// Lets update everything about Interrupts and other things.
254256
// TODO: Need to implement CPU_CYCLES for proper Interrupt timings!
255-
dmaController.Update();
257+
258+
259+
videoController.Update(ticks);
260+
dmaController.Tick();
256261
internalTimer.Update();
262+
}
257263

258-
exe_ins();
264+
public bool BreakpointOccurred()
265+
{
266+
if (Program.emulator.breakPointsList.Count == 0)
267+
return false;
259268

269+
if (Program.emulator.breakPointsList.Contains(Program.emulator.getCPU().get_reg_pc()))
270+
{
271+
Program.emulator.isRunning = false;
272+
return true;
273+
}
274+
return false;
260275
}
261-
// TODO: Need to implement fast timer for RTC support!
276+
262277
public void Start()
263278
{
264279
cpuTask = Task.Run(() =>
265280
{
266281
do
267282
{
268-
/*
269-
// Breakpoints support
270-
if (Program.emulator.breakPointsList.Count != 0)
271-
{
272-
if (Program.emulator.breakPointsList.Contains(Program.emulator.getCPU().get_reg_pc()))
273-
{
274-
Program.emulator.isRunning = false;
275-
break;
276-
}
277-
}
278-
279-
if ((Program.emulator.GetMemory().ReadFromMemory(0xFF40) & 0x80) == 0x80)
280-
{
281-
if(!Program.emulator.getRenderer().isDisplayOn)
282-
Program.emulator.getRenderer().Start();
283-
284-
Program.emulator.getRenderer().Render();
285-
// Display start!
286-
287-
}*/
288-
// TODO: Interrupts Support here
283+
//if (BreakpointOccurred())
284+
// continue;
285+
289286
ExeCycle();
290287

291288
} while (Program.emulator.isRunning);

‎SharpBoy/Emulator/Memory.cs

+10-5
Original file line numberDiff line numberDiff line change
@@ -46,15 +46,20 @@ public void InitializeMemory()
4646

4747
public void WriteToMemory(UInt16 Address, Byte Value)
4848
{
49-
//if (Address < 0x0100) // ROM place
50-
// return;
51-
5249
BaseMemory[Address] = Value;
5350

54-
if(Address == 0xFF40) // LCDC
51+
if(Address == 0xFF46)
5552
{
56-
return;
53+
Program.emulator.getCPU().GetDMAController().StartOAM(Value);
5754
}
55+
/*
56+
switch(Address)
57+
{
58+
case 0xFF46: //DMA Transfer
59+
60+
}
61+
*/
62+
5863
}
5964

6065
public void WriteToMemory(UInt16 Address, Byte[] Values, UInt16 count)

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