have to call it a night.

1 files changed, 213 insertions, 0 deletions

diff --git a/headers/addressing.h b/headers/addressing.h
new file mode 100644
index 0000000..d9d8e98
--- /dev/null
+++ b/headers/addressing.h
@@ -0,0 +1,213 @@
+//	addressing.h
+//	Contains definitions relevant to addressing, as well as fAddress() which returns time, length, value, and address for an instruction function call.
+
+enum Addressing {
+	eImmediate,
+	eAccumulator,
+	eZeroPage,
+	eZeroPageIndexedX,
+	eZeroPageIndexedY,
+	eAbsolute,
+	eAbsoluteIndexedX,
+	eAbsoluteIndexedY,
+	eIndexedIndirect,
+	eIndirectIndexed,
+	eImplied,
+	eIndirectAbsolute,
+	eRelative
+};
+
+typedef int Addressing;
+
+struct AddData{
+	int cycles;
+	int length;
+	address add;
+	byte value;
+};
+
+typedef struct AddData AddData;
+
+#include"instruction-init.h"
+
+//Holds address of current instruction.
+void* current_instruction;
+
+Addressing fAddressGetLength(Addressing addr){
+	switch(addr){
+		case eAbsolute: case eAbsoluteIndexedX: case eAbsoluteIndexedY:
+			return 3;
+		case eAccumulator:
+			return 1;
+		default:
+			return 2;
+	}
+}
+
+AddData fAddress(Addressing addr, short x) {
+	AddData ret;
+
+	// ADDRESS
+
+	switch(addr){
+		case eImplied:
+		case eIndirectAbsolute:
+		case eRelative:
+		case eImmediate:
+		case eAccumulator:
+			ret.add = 0x0000;
+			break;
+
+		case eAbsolute:
+			ret.add = x;
+			break;
+		case eAbsoluteIndexedX:
+			ret.add = (x + X);
+			break;
+		case eAbsoluteIndexedY:
+			ret.add = (x + Y);
+			break;
+
+		case eZeroPage:
+			ret.add = (x & 0x00FF);
+			break;
+		case eZeroPageIndexedX:
+			ret.add = ((x + X) & 0x00FF);
+			break;
+		case eZeroPageIndexedY:
+			ret.add = ((x + Y) & 0x00FF);
+			break;
+
+		case eIndexedIndirect:
+			ret.add = (((address)Memory[x+X+1])<<8) + (Memory[x+X]);
+			break;
+		case eIndirectIndexed:
+			ret.add = (((address)Memory[x+1])<<8) + (Memory[x]) + Y;
+			break;
+	}
+
+	//	VALUE
+
+	switch(addr){
+		case eImplied:
+		case eIndirectAbsolute:
+		case eRelative:
+			break;
+		
+		case eImmediate:
+			ret.value = x;
+			break;
+
+		case eAccumulator:
+			ret.value = acc;
+			break;
+
+		default:
+			ret.value = Memory[ret.add];
+	}
+
+	// LENGTH
+
+	ret.length = fAddressGetLength(addr);
+
+	// CYCLES
+
+	//case &fADC: case &fAND: case &fBIT: case &fCMP: case &fCPX: case &fCPY:	case &fEOR:	case &fLDA:
+	//case &fLDX: case &fLDY: case &fORA: case &fSBC: case &fSTX: case &fSTY:
+
+	if (	current_instruction ==  &fADC || current_instruction ==  &fAND || current_instruction == &fBIT || current_instruction ==  &fCMP || current_instruction ==  &fCPX
+		||	current_instruction ==  &fCPY || current_instruction ==  &fEOR || current_instruction == &fLDA || current_instruction ==  &fLDX || current_instruction ==  &fLDY
+		||	current_instruction ==  &fORA || current_instruction ==  &fSBC || current_instruction == &fSTX || current_instruction ==  &fSTY	){
+		switch(addr){
+			case eImmediate:
+				ret.cycles = 2; break;
+			case eZeroPage:
+				ret.cycles = 3; break;
+			case eZeroPageIndexedX: case eAbsolute: case eAbsoluteIndexedX: case eAbsoluteIndexedY:
+				ret.cycles = 4; break;
+			case eIndexedIndirect:
+				ret.cycles = 6; break;
+			case eIndirectIndexed:
+				ret.cycles = 5; break;
+		}
+	}
+
+	//case &fASL: case &fDEC: case &fINC: case &fLSR: case &fROL: case &fROR:
+	else if(	current_instruction ==  &fASL || current_instruction ==  &fDEC || current_instruction == &fINC
+			||	current_instruction ==  &fLSR || current_instruction ==  &fROL || current_instruction == &fROR	){
+		switch(addr){
+			case eAccumulator:
+				ret.cycles = 2; break;
+			case eZeroPage:
+				ret.cycles = 5; break;
+			case eZeroPageIndexedX: case eAbsolute:
+				ret.cycles = 6; break;
+			case eAbsoluteIndexedX:
+				ret.cycles = 7; break;
+		}
+	}
+
+	//case &fSTA:
+	else if  (current_instruction == &fSTA){
+		switch(addr){
+			case eZeroPage:
+				ret.cycles = 3; break;
+			case eZeroPageIndexedX: case eAbsolute:
+				ret.cycles = 4; break;
+			case eAbsoluteIndexedX: case eAbsoluteIndexedY:
+				ret.cycles = 5; break;
+			case eIndexedIndirect: case eIndirectIndexed:
+				ret.cycles = 6; break;
+		}
+	}
+
+
+	//case &fBRK:
+	else if (current_instruction == &fBRK){
+		ret.cycles = 7;
+	}
+
+
+	//case &fRTI: case &fRTS: case &fJSR:
+	else if (current_instruction == &fRTI || current_instruction == &fRTS || current_instruction == &fJSR){
+		ret.cycles = 6;
+	}
+
+	//case &fJMP:
+	else if (current_instruction == &fJMP){
+		ret.cycles = 5;
+	}
+
+	//case &fPLA: case &fPLP:
+	else if (current_instruction == &fPLA || current_instruction == &fPLP){
+		ret.cycles = 4;
+	}
+
+	//case &fPHA: case &fPHP:
+	else if (current_instruction == &fPHA || current_instruction == &fPHP){
+		ret.cycles = 3;
+	}
+
+	else {
+		ret.cycles = 2;
+	}
+
+
+	// Page Boundary
+
+	//case &fADC: case &fSBC: case &fLDA: case &fLDX: case &fLDY: case &fEOR: case &fAND: case &fORA: case &fCMP:
+	if (	current_instruction ==  &fADC || current_instruction ==  &fSBC || current_instruction == &fLDA || current_instruction ==  &fLDX || current_instruction ==  &fLDY
+		||	current_instruction ==  &fEOR || current_instruction ==  &fAND || current_instruction == &fORA || current_instruction ==  &fCMP ){
+		switch(addr){
+			case eAbsoluteIndexedX: 
+				if ((x & 0xFFFC) != ((x + X) & 0xFFFC)) ret.cycles++; break;
+			case eAbsoluteIndexedY: 
+				if ((x & 0xFFFC) != ((x + Y) & 0xFFFC)) ret.cycles++; break;
+			case eIndirectIndexed:
+				if ((ret.add & 0xFFFC) != (ret.add - Y & 0xFFFC)) ret.cycles++; break;
+		}
+	}
+
+	return ret;
+}
+