diff options
Diffstat (limited to 'contrib/nosefart/nes_apu.c')
| -rw-r--r-- | contrib/nosefart/nes_apu.c | 102 |
1 files changed, 73 insertions, 29 deletions
diff --git a/contrib/nosefart/nes_apu.c b/contrib/nosefart/nes_apu.c index 4a2ed8f4d..474e2ca1a 100644 --- a/contrib/nosefart/nes_apu.c +++ b/contrib/nosefart/nes_apu.c @@ -57,6 +57,11 @@ static int8 noise_long_lut[APU_NOISE_32K]; static int8 noise_short_lut[APU_NOISE_93]; #endif /* !REALTIME_NOISE */ +/* $$$ ben : last error */ +#define SET_APU_ERROR(APU,X) \ +if (APU) (APU)->errstr = "apu: " X; else + +#define APU_MIX_ENABLE(BIT) (apu->mix_enable&(1<<(BIT))) /* vblank length table used for rectangles, triangle, noise */ static const uint8 vbl_length[32] = @@ -102,27 +107,32 @@ const int dmc_clocks[16] = /* ratios of pos/neg pulse for rectangle waves */ static const int duty_lut[4] = { 2, 4, 8, 12 }; -#if 0 /* unused */ -static void apu_setcontext(apu_t *src_apu) + +void apu_setcontext(apu_t *src_apu) { apu = src_apu; + /* $$$ ben reset eoor string here. */ + SET_APU_ERROR(apu,"no error"); } -#endif /* ** Simple queue routines */ #define APU_QEMPTY() (apu->q_head == apu->q_tail) -static void apu_enqueue(apudata_t *d) +static int apu_enqueue(apudata_t *d) { ASSERT(apu); apu->queue[apu->q_head] = *d; apu->q_head = (apu->q_head + 1) & APUQUEUE_MASK; - if (APU_QEMPTY()) + if (APU_QEMPTY()) { log_printf("apu: queue overflow\n"); + SET_APU_ERROR(apu,"queue overflow"); + return -1; + } + return 0; } static apudata_t *apu_dequeue(void) @@ -131,19 +141,32 @@ static apudata_t *apu_dequeue(void) ASSERT(apu); - if (APU_QEMPTY()) - log_printf("apu: queue empty\n"); - + if (APU_QEMPTY()) { + log_printf("apu: queue empty\n"); + SET_APU_ERROR(apu,"queue empty"); + /* $$$ ben : should return 0 ??? */ + } loc = apu->q_tail; apu->q_tail = (apu->q_tail + 1) & APUQUEUE_MASK; return &apu->queue[loc]; } -void apu_setchan(int chan, boolean enabled) +int apu_setchan(int chan, boolean enabled) { - ASSERT(apu); - apu->mix_enable[chan] = enabled; + const unsigned int max = 6; + int old; + + ASSERT(apu); + if ((unsigned int)chan >= max) { + SET_APU_ERROR(apu,"channel out of range"); + return -1; + } + old = (apu->mix_enable>>chan) & 1; + if (enabled != (boolean)-1) { + apu->mix_enable = (apu->mix_enable & ~(1<<chan)) | ((!!enabled)<<chan); + } + return old; } /* emulation of the 15-bit shift register the @@ -977,13 +1000,13 @@ void apu_process(void *buffer, int num_samples) elapsed_cycles += APU_FROM_FIXED(apu->cycle_rate); accum = 0; - if (apu->mix_enable[0]) accum += apu_rectangle(&apu->rectangle[0]); - if (apu->mix_enable[1]) accum += apu_rectangle(&apu->rectangle[1]); - if (apu->mix_enable[2]) accum += apu_triangle(&apu->triangle); - if (apu->mix_enable[3]) accum += apu_noise(&apu->noise); - if (apu->mix_enable[4]) accum += apu_dmc(&apu->dmc); + if (APU_MIX_ENABLE(0)) accum += apu_rectangle(&apu->rectangle[0]); + if (APU_MIX_ENABLE(1)) accum += apu_rectangle(&apu->rectangle[1]); + if (APU_MIX_ENABLE(2)) accum += apu_triangle(&apu->triangle); + if (APU_MIX_ENABLE(3)) accum += apu_noise(&apu->noise); + if (APU_MIX_ENABLE(4)) accum += apu_dmc(&apu->dmc); - if (apu->ext && apu->mix_enable[5]) accum += apu->ext->process(); + if (apu->ext && APU_MIX_ENABLE(5)) accum += apu->ext->process(); /* do any filtering */ if (APU_FILTER_NONE != apu->filter_type) @@ -1012,11 +1035,12 @@ void apu_process(void *buffer, int num_samples) /* signed 16-bit output, unsigned 8-bit */ if (16 == apu->sample_bits) { - *((int16 *) buffer) = (int16) accum; - buffer = (int16 *) buffer + 1; - } else { - *((uint8 *) buffer) = (accum >> 8) ^ 0x80; - buffer = (int8 *) buffer + 1; + *(int16 *)(buffer) = (int16) accum; + buffer += sizeof(int16); + } + else { + *(uint8 *)(buffer) = (accum >> 8) ^ 0x80; + buffer += sizeof(uint8); } } @@ -1025,10 +1049,18 @@ void apu_process(void *buffer, int num_samples) } /* set the filter type */ -void apu_setfilter(int filter_type) +/* $$$ ben : + * Add a get feature (filter_type == -1) and returns old filter type + */ +int apu_setfilter(int filter_type) { + int old; ASSERT(apu); - apu->filter_type = filter_type; + old = apu->filter_type; + if (filter_type != -1) { + apu->filter_type = filter_type; + } + return old; } void apu_reset(void) @@ -1057,7 +1089,7 @@ void apu_reset(void) apu->ext->reset(); } -static void apu_build_luts(int num_samples) +void apu_build_luts(int num_samples) { int i; @@ -1090,12 +1122,15 @@ static void apu_setactive(apu_t *active) apu_t *apu_create(int sample_rate, int refresh_rate, int sample_bits, boolean stereo) { apu_t *temp_apu; - int channel; +/* int channel; */ temp_apu = malloc(sizeof(apu_t)); if (NULL == temp_apu) return NULL; + /* $$$ ben : safety net, in case we forgot to init something */ + memset(temp_apu,0,sizeof(apu_t)); + SET_APU_ERROR(temp_apu,"no error"); temp_apu->sample_rate = sample_rate; temp_apu->refresh_rate = refresh_rate; temp_apu->sample_bits = sample_bits; @@ -1114,8 +1149,9 @@ apu_t *apu_create(int sample_rate, int refresh_rate, int sample_bits, boolean st apu_setactive(temp_apu); apu_reset(); - for (channel = 0; channel < 6; channel++) - apu_setchan(channel, TRUE); + temp_apu->mix_enable = 0x3F; +/* for (channel = 0; channel < 6; channel++) */ +/* apu_setchan(channel, TRUE); */ apu_setfilter(APU_FILTER_LOWPASS); @@ -1137,15 +1173,23 @@ void apu_destroy(apu_t *src_apu) } } -void apu_setext(apu_t *src_apu, apuext_t *ext) +int apu_setext(apu_t *src_apu, apuext_t *ext) { ASSERT(src_apu); + /* $$$ ben : seem cleaner like this */ + if (src_apu->ext) { + src_apu->ext->shutdown(); + } + src_apu->ext = ext; /* initialize it */ if (src_apu->ext) src_apu->ext->init(); + + /* $$$ ben : May be one day extension int () will return error code */ + return 0; } /* this exists for external mixing routines */ |