Add TAX instruction

src/6502/6502.h

@@ -26,6 +26,9 @@ typedef unsigned short word; // 16 bit
 #define INS_LDY_ABS 0xAC // LDY Absolute
 #define INS_LDY_ABSX 0xBC // LDY Absolute,X
 
+#define INS_TAX 0xAA // TAX Implied
+#define INS_TAY 0xA8 // TAY Implied
+
 #define INS_JSR 0x20 // JSR
 #define INS_RTS 0x60 // RTS
 

src/6502/main.c

@@ -127,7 +127,12 @@ void execute() {
 				cpu.Z = (cpu.Y == 0);
 				cpu.N = (cpu.Y & 0b1000000) > 0;
 				break;
-
+		        case INS_TAX:
+			        cpu.X = cpu.A;
+				cpu.Z = (cpu.X == 0);
+				cpu.N = (cpu.X & 0b1000000) > 0;
+				cpu.PC++;
+			        break;
 			case INS_JSR:
 				word jsr_addr = fetch_word();
 				write_word(cpu.PC - 1, cpu.SP);

src/6502/test.bin

@@ -1 +1 @@
-ｩVｩdｩB
+ｩUｪ