Memory.cpp

#include <iostream>
#include <iomanip>
#include "Memory.h"
// btw baddy stands for byte address
Memory::Memory(){
	reset();
}

void Memory::reset(void){
	for(int i = 0; i < MEMORY_SIZE; i++){
		mem[i] = 0;
	}
	lastUsed = 0;
	memError = false;
}

/*
 * Trace
 * Returns the last utilized memory location.
 */
uint16_t Memory::trace(){
	return lastUsed;
}

/*
 * getByte
 * Returns a single byte in memory, given a 16-bit byte address.
 */
uint8_t Memory::getByte(uint16_t baddy)
{
	lastUsed = baddy;
	if (baddy >= 0 && baddy < MEMORY_SIZE){
		return mem[baddy];
	}
	else{
		memError = true;
		return 0;
	}
}

/*
 * getWord
 * returns a 16-bit value from memory, given a 16-bit byte address.
 */
uint16_t Memory::getWord(uint16_t baddy){
	lastUsed = baddy;
	if(baddy >= 0 && baddy < MEMORY_SIZE - 1){
		return (mem[baddy] << 8) + mem[baddy + 1];
	}
	else{
		memError = true;
		return 0;
	}
}

/*
 * getTile
 * Returns a pointer to the start of a tile (16 bytes), given a 16-bit byte address.
 */
uint8_t * Memory::getTile(uint16_t baddy)
{
	lastUsed = baddy;
	if (VRAM <= baddy && (baddy + 15) <= VRAM_END){
		return &(mem[baddy]);
	}
	else
	{
		memError = true;
		return 0;
	}
}

uint16_t Memory::getTileRow(uint16_t baddy){
	lastUsed = baddy;
	if(VRAM <= baddy && (baddy + 15) <= VRAM_END){
		uint16_t final = 0;
		final += mem[baddy];
		final += (mem[baddy+1]) << 8;
		return final;
	}
	else{
		memError = true;
		return 0;
	}
}

/*
 * putByte
 * Puts a single byte into memory, given a 16-bit byte address.
 */
void Memory::putByte(uint16_t baddy, uint8_t val)
{
	lastUsed = baddy;
	if (baddy < MEMORY_SIZE){
		mem[baddy] = val;
	}
	else{
		memError = true;
	}

}

/*
 * putTile
 * Puts a tile (16 bytes) into memory, given a 16-bit byte address.
 */
void Memory::putTile(uint16_t baddy, uint8_t val[16]){
	lastUsed = baddy;
	if (VRAM <= baddy && (baddy + 15) <= VRAM_END){	
		for (int i = 0; i < 16; i++) mem[baddy + i] = val[i];
	}
	else{
		memError = true;
	}
}

/*
 * dumpROM
 * Dumps the contents in memory from range 0x100 to 0x3FFF (CART_HEADER to ROM_END).
 * Formats into 16-byte chunks with the starting address prefixed.
 */
void Memory::dump(int start, int end){
	// uint8_t prevLine[16];
	uint8_t currLine[16];
	// initializing arrays to 0
	for (int i = 0; i < 16; i++){
		// prevLine[i] = 0;
		currLine[i] = 0;
	}
	for (int i = start; i < end; i+=16){
		for (int j = 0; j < 16; j++){
			currLine[j] = getByte(i + j);
		}
			// printing out the correct address and formatting
			std::cout << std::endl << std::setw(4) << std::setfill('0') << std::hex << i << ": ";
			// printing out the contents of the address in 16 bytes per line
			for (int j = 0; j < 16; j++){
				std::cout << std::setw(2) << std::setfill('0') << std::hex << static_cast<int>(currLine[j]) << " ";			
			} 
	}
	std::cout << std::endl;
}

/*
 * isMemError
 * Returns status of memory error flag, so we can tell if our abort was due to memory accesses.
 */
bool Memory::isMemError(void){
	return memError;
}