view wave.c @ 921:2be771c4dfbd

After reviewing the results of my test ROM again it seems pretty clear that the VBlank flag gets set at the same time as the vcounter changes
author Michael Pavone <pavone@retrodev.com>
date Tue, 26 Jan 2016 19:23:10 -0800
parents 6e9d1a8c1b08
children efc75ea79164
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/*
 Copyright 2013 Michael Pavone
 This file is part of BlastEm.
 BlastEm is free software distributed under the terms of the GNU General Public License version 3 or greater. See COPYING for full license text.
*/
#include "wave.h"
#include <stddef.h>
#include <string.h>

int wave_init(FILE * f, uint32_t sample_rate, uint16_t bits_per_sample, uint16_t num_channels)
{
	wave_header header;
	memcpy(header.chunk.id, "RIFF", 4);
	memcpy(header.chunk.format, "WAVE", 4);
	header.chunk.size = 0; //This will be filled in later
	memcpy(header.format_header.id, "fmt ", 4);
	header.format_header.size = sizeof(wave_header) - (sizeof(header.chunk) + sizeof(header.data_header) + sizeof(header.format_header));
	header.audio_format = 1;
	header.num_channels = num_channels;
	header.sample_rate = sample_rate;
	header.byte_rate = sample_rate * num_channels * (bits_per_sample/8);
	header.block_align = num_channels * (bits_per_sample/8);
	header.bits_per_sample = bits_per_sample;
	memcpy(header.data_header.id, "data", 4);
	header.data_header.size = 0;//This will be filled in later;
	return fwrite(&header, 1, sizeof(header), f) == sizeof(header);
}

int wave_finalize(FILE * f)
{
	uint32_t size = ftell(f);
	fseek(f, offsetof(wave_header, chunk.size), SEEK_SET);
	size -= 8;
	if (fwrite(&size, sizeof(size), 1, f) != 1) {
		fclose(f);
		return 0;
	}
	fseek(f, offsetof(wave_header, data_header.size), SEEK_SET);
	size -= 36;
	if (fwrite(&size, sizeof(size), 1, f) != 1) {
		fclose(f);
		return 0;
	}
	fclose(f);
	return 1;
}