Merge pull request #3 from viniciusfdasilva/dev

Dev

src/chip8.v

@@ -63,6 +63,7 @@ const num_of_registers = 16
 const f                = 15
 
 struct Chip8{
+	cpu_clock u8 = 9
 	pub mut:
 		ram  [mem_size]u8
 		v [num_of_registers]u8
@@ -74,6 +75,7 @@ struct Chip8{
 		sound_timer u8
 		is_draw     bool
 		key         u8
+		cycles      u8
 }
 
 fn (mut chip Chip8) start_cpu(){
@@ -202,7 +204,7 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 		}
 
 		0x6000 {
-			x  = (instruction & 0xF00) >> 8
+			x  = (instruction & 0x0F00) >> 8
 			nn = instruction & 0x00FF
 
 			chip.v[x] = u8(nn)
@@ -210,7 +212,7 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 		}
 
 		0x7000 {
-			x  = (instruction & 0xF00) >> 8
+			x  = (instruction & 0x0F00) >> 8
 			nn = instruction & 0x00FF
 
 			chip.v[x] += u8(nn)
@@ -253,25 +255,30 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 						chip.v[f] = 0
 					}
 
-					chip.v[x] = xy
+					chip.v[x] = (xy & 0xFF)
 					// Adds VY to VX. VF is set to 1 when there's an overflow, and to 0 when there is not.
 				}
 
 				0x05 {
-					xy := chip.v[x] - chip.v[y]
 
-					if chip.v[x] >= chip.v[y] {
+					if chip.v[x] > chip.v[y] {
 						chip.v[f] = 1
 					}else{
 						chip.v[f] = 0
 					}
 
-					chip.v[x] = xy
+					chip.v[x] -= chip.v[y]
 					// VY is subtracted from VX. VF is set to 0 when there's an underflow, and 1 when there is not. (i.e. VF set to 1 if VX >= VY and 0 if not)
 				}
 
 				0x06 {
-					chip.v[f] = (chip.v[x] & 0xF0) >> 7
+					if chip.v[x] % 2 == 1 {
+        				chip.v[f] = 1;
+    				}
+    				else {
+    				    chip.v[f] = 0;
+    				}
+
 					chip.v[x] = chip.v[x] >> 1
 					// Stores the least significant bit of VX in VF and then shifts VX to the right by 1
 				}
@@ -280,7 +287,7 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 
 					xy := chip.v[y] - chip.v[x]
 
-					if chip.v[y] >= chip.v[x] {
+					if chip.v[y] > chip.v[x] {
 						chip.v[f] = 1
 					}else{
 						chip.v[f] = 0
@@ -292,9 +299,14 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 
 				0x0E {
 
-					chip.v[f] = (chip.v[x] & 0xF0) >> 7
+					 if (chip.v[x] & 10000000) == 1 {
+        				chip.v[f] = 1;
+    				}
+    				else {
+    				    chip.v[f] = 0;
+    				}
 
-					chip.v[x] = chip.v[x] >> 1
+					chip.v[x] = chip.v[x] << 1
 					// Stores the most significant bit of VX in VF and then shifts VX to the left by 1.
 				}
 
@@ -341,8 +353,8 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 			y = (instruction & 0x00F0) >> 4
 			n = (instruction & 0x000F)
 
-			mut regvy := u16(chip.v[y] % chip.screen.display_height)
+			mut regvy := u16(chip.v[y])
-			mut regvx := u16(chip.v[x] % chip.screen.display_width)
+			mut regvx := u16(chip.v[x])
 
 			chip.v[f] = 0
 
@@ -406,35 +418,36 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 
 				0x18{
 					chip.sound_timer = chip.v[x]
-					}
+				}
 
 				0x1E{
 					chip.i += chip.v[x]
 				}
 
 				0x29{
-					chip.i = chip.v[x] * 5
+					chip.i = u16(chip.v[x] * 0x5)
 				}
 
 				0x33{
-					chip.ram[chip.i] = chip.v[x] / 100;
+
-					chip.ram[chip.i + 1] = (chip.v[x] / 10) % 10
+					chip.ram[chip.i] = u8(chip.v[x] / 100)
-					chip.ram[chip.i + 2] = chip.v[x] % 10;
+					chip.ram[chip.i + 1] = u8((u8(chip.v[x] / 10)) % 10)
+					chip.ram[chip.i + 2] = u8(chip.v[x] % 100) % 10
 				}
 
 				0x55{
 
-					for i := 0; i <= x; i++ {
+					for i := chip.v[0]; i <= x; i++ {
 						chip.ram[chip.i + i] = chip.v[i]
 					}
-					chip.i = u16(chip.i + x + 1)
+					chip.i = u16(x + 1)
 				}
 
 				0x65{
-					for i := 0; i <= x; i++ {
+					for i := chip.v[0]; i <= x; i++ {
-						chip.v[x] = chip.ram[chip.i + x]
+						chip.v[x] = chip.ram[chip.i + i]
 					}
-					chip.i = u16(chip.i + x + 1)
+					chip.i = u16(x + 1)
 				}
 
 				else {
@@ -450,6 +463,10 @@ fn (mut chip Chip8) decode_and_run(instruction u16) {
 	if !is_jump { chip.pc += 2 }
 }
 
+fn (mut chip Chip8) update_timers(){
+	if chip.delay_timer > 0 { chip.delay_timer-- }
+	if chip.sound_timer > 0 { chip.sound_timer-- }
+}
 
 fn (mut chip Chip8) set_key(key int){
 	chip.key = u8(keyboard[key])

src/main.v

@@ -13,7 +13,7 @@ struct Emulator{
 }
 
 fn (mut emulator Emulator) draw_block(i f32, j f32) {
-	emulator.graphic.draw_rect_filled(j,i, f32(20-1), f32(20-1), gx.rgb(0,255,0))
+	emulator.graphic.draw_rect_filled(j,i, f32(20), f32(20), gx.rgb(0,255,0))
 }
 
 fn (mut emulator Emulator) load_rom() !{
@@ -44,6 +44,8 @@ fn frame(mut emulator Emulator){
 	emulator.graphic.begin()
 
 	emulator.chip8.run()
+	emulator.chip8.cycles++;
+	emulator.chip8.update_timers()
 	
 	display_height := emulator.chip8.screen.display_height
 	display_width  := emulator.chip8.screen.display_width
@@ -54,10 +56,15 @@ fn frame(mut emulator Emulator){
 			pixel := emulator.chip8.screen.display[y][x]
 			
 			if pixel == 1 {
-				emulator.draw_block(f32((y-1)*20), f32((x-1)*20))
+				emulator.draw_block(f32((y)*20), f32((x)*20))
 			}
 		}
 	}
+
+	if emulator.chip8.cpu_clock == emulator.chip8.cycles {
+		emulator.chip8.cycles = 0
+	}
+
 	emulator.graphic.end()
 }
 
@@ -65,80 +72,6 @@ fn (mut emulator Emulator) show_display(){
 	emulator.graphic.run()
 }
 
-//fn (emulator Emulator) keyboard(input string) !string{
-//
-//	match input {
-//		'1' {
-//			return 0x0001
-//		},
-//
-//		'2' {
-//
-//		},
-//
-//		'3' {
-//
-//		},
-//
-//		'4' {
-//
-//		},
-//
-//		'Q', 'q' {
-//
-//		},
-//
-//		'W', 'w' {
-//
-//		},
-//
-//		'E', 'e' {
-//
-//		},
-//
-//		'R', 'r' {
-//
-//		},
-//
-//		'A', 'a' {
-//
-//		},
-//
-//		'S', 's' {
-//
-//		},
-//
-//		'D', 'd' {
-//
-//		},
-//
-//		'F', 'f' {
-//
-//		},
-//
-//		'Z', 'z' {
-//
-//		},
-//
-//		'X', 'x' {
-//
-//		},
-//
-//		'C', 'c' {
-//
-//		},
-//
-//		'V', 'v' {
-//
-//		},
-//
-//		else {
-//			panic('Invalid key!')
-//		}
-//	}
-//	
-//}
-
 fn is_graphic() bool{
 	return os.environ()['DISPLAY'] != ''
 }