diff --git a/include/audio.h b/include/audio.h index db3c1e8..67aa38a 100644 --- a/include/audio.h +++ b/include/audio.h @@ -117,6 +117,11 @@ typedef struct { float right_history[384]; u32 right_index; + u8 sq1_sample_val; + u32 sq1_write_index; + u32 sq1_read_index; + u8 sq1_audio_buffer[4096]; + } audio_context; void audio_init(); diff --git a/lib/audio.c b/lib/audio.c index 1dac96c..29cc87a 100644 --- a/lib/audio.c +++ b/lib/audio.c @@ -5,11 +5,13 @@ #include #include +#include #define SAMPLE_RATE 44100 #define FRAMES_PER_BUFFER 64 #define TIME_PER_SAMPLE 1.0f / (SAMPLE_RATE/1000.0f/1000.0f) #define TIME_PER_AUDIO_TICK 1.0f / (1048576.0f/1000.0f/1000.0f) +#define AUDIO_TICKS_PER_SAMPLE 1048576.0f / SAMPLE_RATE #define TIME_PER_WAVE_TICK 1.0f / (2097152.0f/1000.0f/1000.0f) #define LFSR_BASE_CLOCK 262144.0f @@ -31,6 +33,7 @@ static float right_cap = 0.0f; static int history_timer = 0; const int history_interval = 5; static int lfsr_clocks = 0; +static double write_index = 0; const u8 square_sample_00[8] = { 0x0, @@ -90,6 +93,12 @@ static int audio_callback(const void* input_uffer, void *output_buffer, void *userData ) { float *out = (float *)output_buffer; for(int i = 0; i < framesPerBuffer; i++) { + write_index = write_index + AUDIO_TICKS_PER_SAMPLE; + ctx.sq1_read_index = (int)write_index; + if(ctx.sq1_read_index > ctx.sq1_write_index) { + ctx.sq1_read_index = ctx.sq1_write_index-1; + write_index = ctx.sq1_read_index; + } if(ppu_get_context()->paused) { *out++ = 0; *out++ = 0; @@ -100,13 +109,13 @@ static int audio_callback(const void* input_uffer, void *output_buffer, audio_time += TIME_PER_SAMPLE; wave_time += TIME_PER_SAMPLE; for(;audio_time >= TIME_PER_AUDIO_TICK;audio_time -= TIME_PER_AUDIO_TICK) { - ctx.sq1_period_timer++; + //ctx.sq1_period_timer++; ctx.sq2_period_timer++; - if(ctx.sq1_period_timer >= 0x800) { - ctx.sq1_period_timer = ctx.sq1_period_reset; - ctx.sq1_sample = (ctx.sq1_sample + 1) % 8; - } + //if(ctx.sq1_period_timer >= 0x800) { + // ctx.sq1_period_timer = ctx.sq1_period_reset; + // ctx.sq1_sample = (ctx.sq1_sample + 1) % 8; + //} if(ctx.sq2_period_timer >= 0x800) { ctx.sq2_period_timer = ctx.sq2_period_reset; ctx.sq2_sample = (ctx.sq2_sample + 1) % 8; @@ -158,7 +167,8 @@ static int audio_callback(const void* input_uffer, void *output_buffer, if(ctx.ch1_dac){ sq1_val = -1; if(ctx.sq1_enable) { - sq1_val = ((float)ctx.sq1_volume/15.0f) * (((float)(square_sample[ctx.sq1_duty][ctx.sq1_sample]) - 7.5f)/7.5f); + //sq1_val = ((float)ctx.sq1_volume/15.0f) * (((float)(square_sample[ctx.sq1_duty][ctx.sq1_sample]) - 7.5f)/7.5f); + sq1_val = ((float)ctx.sq1_volume/15.0f) * (((float)(ctx.sq1_audio_buffer[ctx.sq1_read_index % 4096]) - 7.5f)/7.5f); if(ctx.ch1_left) { left += sq1_val; }else { @@ -177,7 +187,7 @@ static int audio_callback(const void* input_uffer, void *output_buffer, if(ctx.ch2_dac){ sq2_val = -1; if(ctx.sq2_enable) { - sq2_val = ((float)ctx.sq2_volume/15.0f) * (((float)(square_sample[ctx.sq2_duty][ctx.sq2_sample]) - 7.5f)/7.5f); + //sq2_val = ((float)ctx.sq2_volume/15.0f) * (((float)(square_sample[ctx.sq2_duty][ctx.sq2_sample]) - 7.5f)/7.5f); if(ctx.ch2_left) { left += sq2_val; }else { @@ -206,7 +216,7 @@ static int audio_callback(const void* input_uffer, void *output_buffer, if(ctx.ch3_volume == 0b11) { shift = 2; } - ch3_val = (((float)(ctx.ch3_last_sample >> shift) - 7.5f)/7.5f); + //ch3_val = (((float)(ctx.ch3_last_sample >> shift) - 7.5f)/7.5f); if(ctx.ch3_left) { left += ch3_val; //printf("left: %d\n", ctx.ch3_volume); @@ -226,7 +236,7 @@ static int audio_callback(const void* input_uffer, void *output_buffer, if(ctx.ch4_dac){ ch4_val = -1; if(ctx.ch4_enable) { - ch4_val = ((ctx.ch4_lfsr & 0b1) == 0b1) ? (((float)ctx.ch4_volume - 7.5f)/7.5f) : -1.0f; + //ch4_val = ((ctx.ch4_lfsr & 0b1) == 0b1) ? (((float)ctx.ch4_volume - 7.5f)/7.5f) : -1.0f; if(ctx.ch4_left) { left += ch4_val; //printf("left: %d\n", ctx.ch3_volume); @@ -368,6 +378,7 @@ void audio_init(){ ctx.sq2_env_direction = false; ctx.sq2_env_pace = 0x0; ctx.sq2_env_timer = 0x0; + ctx.sq1_write_index = 1; err = Pa_Initialize(); if (err != paNoError) goto error; @@ -412,6 +423,24 @@ void sq1_sweep() { static int change = 1; static u32 ticks = 0; static u32 start, end = 0; +static u32 period_tick; + +void audio_period_tick() { + period_tick++; + if(period_tick % 2 == 0){ + ctx.sq1_period_timer++; + + if(ctx.sq1_period_timer >= 0x800) { + ctx.sq1_period_timer = ctx.sq1_period_reset; + ctx.sq1_sample = (ctx.sq1_sample + 1) % 8; + } + if(ctx.sq1_write_index > ctx.sq1_read_index){ + ctx.sq1_audio_buffer[(ctx.sq1_write_index++)%4096] = square_sample[ctx.sq1_duty][ctx.sq1_sample]; + } else { + printf("buffer overflow\n"); + } + } +} void audio_tick(){ u32 prev_ticks = ticks; diff --git a/lib/timer.c b/lib/timer.c index a45a675..bc866e4 100644 --- a/lib/timer.c +++ b/lib/timer.c @@ -44,7 +44,7 @@ void timer_tick() { } if((prev_div & (1 << 1)) && (!(ctx.div & (1 << 1)))){ - //audio_period_tick(); + audio_period_tick(); } }