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#include"apple.h"

void AppleOn(){
	Memory = calloc(MEMORY_SIZE, sizeof(byte));
	InitInstructionTable();

	// Load ROM.
	FILE *ROM = fopen ("rom.bin", "rb");
	if (ROM == NULL) {
		printf("\n\rROM does not exist.\n");
		abort();
	}
	for (int i = 0; i < 256; i++) {
		Memory[0xFF00+i] = fgetc(ROM);
	}
}

void AppleReset(){
	acc = 0; X = 0; Y = 0; P = 0; S = 0;
	idata.cycles = 0; idata.length = 0; idata.add = 0; idata.value = 0;
	PC = 0xFF00;
	free(Memory);
	Memory = calloc(MEMORY_SIZE, sizeof(byte));
}

byte ToAppleAscii(char x)
{
	if (x < 0x20 || x >= 0x60)
		return -1;
	if (x >= 0x40)
		x -= 0x40;
	return x;
}

byte ToAscii(char x)
{
	if (x < 0x20)
		x += 0x40;
	return x;
}


byte GetMemory(address x){
	switch(x)
	{
		// I opted to make the kbd return successfully at all times for the sake of simplicity.
		// This is not technically "accurate" behavior however.
	case KBD:
		return 0b10000000 | ToAppleAscii(UserInput());
	case KBD_CR: case DSP:
		return 0b10000000;
	default:
		return Memory[x];
	}

}

void SetMemory(address x, byte y){
	Memory[x] = y;
}