From 692a5e467470ca26ff06391899aa8f5eecbf5d1b Mon Sep 17 00:00:00 2001 From: Aaron Giles Date: Mon, 5 May 2008 07:10:47 +0000 Subject: Spacing and version bump. --- src/emu/sound/ay8910.c | 54 +++++++++++++++++++++++++------------------------- 1 file changed, 27 insertions(+), 27 deletions(-) (limited to 'src/emu/sound/ay8910.c') diff --git a/src/emu/sound/ay8910.c b/src/emu/sound/ay8910.c index aa717037b34..9c3409e56b3 100644 --- a/src/emu/sound/ay8910.c +++ b/src/emu/sound/ay8910.c @@ -66,34 +66,34 @@ where used to calibrate channel mixing for the YM2149. This was done using a least square approach using a fixed RL of 1K Ohm. For the AY measurements cited in e.g. openmsx as "Hacker Kay" for a single -channel were taken. These were normalized to 0 ... 65535 and consequently +channel were taken. These were normalized to 0 ... 65535 and consequently adapted to an offset of 0.2V and a VPP of 1.3V. These measurements are in line e.g. with the formula used by pcmenc for the volume: vol(i) = exp(i/2-7.5). The following is documentation from the code moved here and amended to reflect the changes done: - + Careful studies of the chip output prove that the chip counts up from 0 -until the counter becomes greater or equal to the period. This is an -important difference when the program is rapidly changing the period to -modulate the sound. This is worthwhile noting, since the datasheets +until the counter becomes greater or equal to the period. This is an +important difference when the program is rapidly changing the period to +modulate the sound. This is worthwhile noting, since the datasheets say, that the chip counts down. Also, note that period = 0 is the same as period = 1. This is mentioned in the YM2203 data sheets. However, this does NOT apply to the Envelope period. In that case, period = 0 is half as period = 1. Envelope shapes: - C AtAlH - 0 0 x x \___ - 0 1 x x /___ - 1 0 0 0 \\\\ - 1 0 0 1 \___ - 1 0 1 0 \/\/ - 1 0 1 1 \``` - 1 1 0 0 //// - 1 1 0 1 /``` - 1 1 1 0 /\/\ - 1 1 1 1 /___ + C AtAlH + 0 0 x x \___ + 0 1 x x /___ + 1 0 0 0 \\\\ + 1 0 0 1 \___ + 1 0 1 0 \/\/ + 1 0 1 1 \``` + 1 1 0 0 //// + 1 1 0 1 /``` + 1 1 1 0 /\/\ + 1 1 1 1 /___ The envelope counter on the AY-3-8910 has 16 steps. On the YM2149 it has twice the steps, happening twice as fast. @@ -191,7 +191,7 @@ struct _ay8910_context /************************************* * - * Static + * Static * *************************************/ @@ -263,7 +263,7 @@ static const ay_ym_param ay8910_param = /************************************* * - * Inline + * Inline * *************************************/ @@ -380,7 +380,7 @@ INLINE UINT16 mix_3D(ay8910_context *psg) /************************************* * - * Static functions + * Static functions * *************************************/ @@ -547,7 +547,7 @@ static void ay8910_update(void *param,stream_sample_t **inputs, stream_sample_t if (psg->holding == 0) { psg->count_env++; - if (psg->count_env >= ENVELOPE_PERIOD(psg) * psg->step ) + if (psg->count_env >= ENVELOPE_PERIOD(psg) * psg->step ) { psg->count_env = 0; psg->env_step--; @@ -620,9 +620,9 @@ static void build_mixer_table(ay8910_context *psg) build_single_table(psg->intf->res_load[chan], psg->par_env, normalize, psg->env_table[chan], 0); } /* - * The previous implementation added all three channels up instead of averaging them. - * The factor of 3 will force the same levels if normalizing is used. - */ + * The previous implementation added all three channels up instead of averaging them. + * The factor of 3 will force the same levels if normalizing is used. + */ build_3D_table(psg->intf->res_load[0], psg->par, psg->par_env, normalize, 3, psg->zero_is_off, psg->vol3d_table); } @@ -651,8 +651,8 @@ static void ay8910_statesave(ay8910_context *psg, int sndindex) /************************************* * - * Public functions - * + * Public functions + * * used by e.g. YM2203, YM2210 ... * *************************************/ @@ -813,7 +813,7 @@ int ay8910_read_ym(void *chip) /************************************* * * Sound Interface - * + * *************************************/ static void *ay8910_start(int sndindex, int clock, const void *config) @@ -948,7 +948,7 @@ void ymz294_get_info(void *token, UINT32 state, sndinfo *info) /************************************* * * Read/Write Handlers - * + * *************************************/ READ8_HANDLER( AY8910_read_port_0_r ) { return ay8910_read_ym(sndti_token(SOUND_AY8910, 0)); } -- cgit v1.2.3-70-g09d2