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-rw-r--r--src/emu/sound/beep.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/src/emu/sound/beep.c b/src/emu/sound/beep.c
new file mode 100644
index 00000000000..1465c964eb8
--- /dev/null
+++ b/src/emu/sound/beep.c
@@ -0,0 +1,197 @@
+/***************************************************************************
+
+ beep.c
+
+ This is used for computers/systems which can only output a constant tone.
+ This tone can be turned on and off.
+ e.g. PCW and PCW16 computer systems
+ KT - 25-Jun-2000
+
+ Sound handler
+
+****************************************************************************/
+
+#include "sndintrf.h"
+#include "sound/beep.h"
+#include "streams.h"
+
+
+#define BEEP_RATE 48000
+
+
+struct beep_sound
+{
+ sound_stream *stream; /* stream number */
+ int enable; /* enable beep */
+ int frequency; /* set frequency - this can be changed using the appropiate function */
+ int incr; /* initial wave state */
+ INT16 signal; /* current signal */
+};
+
+
+
+/*************************************
+ *
+ * Stream updater
+ *
+ *************************************/
+
+static void beep_sound_update(void *param,stream_sample_t **inputs, stream_sample_t **_buffer,int length)
+{
+ struct beep_sound *bs = (struct beep_sound *) param;
+ stream_sample_t *buffer = _buffer[0];
+ INT16 signal = bs->signal;
+ int clock = 0, rate = BEEP_RATE / 2;
+
+ /* get progress through wave */
+ int incr = bs->incr;
+
+ if (bs->frequency > 0)
+ clock = bs->frequency;
+
+ /* if we're not enabled, just fill with 0 */
+ if ( !bs->enable || clock == 0 )
+ {
+ memset( buffer, 0, length * sizeof(*buffer) );
+ return;
+ }
+
+ /* fill in the sample */
+ while( length-- > 0 )
+ {
+ *buffer++ = signal;
+ incr -= clock;
+ while( incr < 0 )
+ {
+ incr += rate;
+ signal = -signal;
+ }
+ }
+
+ /* store progress through wave */
+ bs->incr = incr;
+ bs->signal = signal;
+}
+
+
+
+/*************************************
+ *
+ * Sound handler start
+ *
+ *************************************/
+
+static void *beep_start(int sndindex, int clock, const void *config)
+{
+ struct beep_sound *pBeep;
+
+ pBeep = auto_malloc(sizeof(*pBeep));
+ memset(pBeep, 0, sizeof(*pBeep));
+
+ pBeep->stream = stream_create(0, 1, BEEP_RATE, pBeep, beep_sound_update );
+ pBeep->enable = 0;
+ pBeep->frequency = 3250;
+ pBeep->incr = 0;
+ pBeep->signal = 0x07fff;
+ return pBeep;
+}
+
+
+
+/*************************************
+ *
+ * changing state to on from off will restart tone
+ *
+ *************************************/
+
+void beep_set_state( int num, int on )
+{
+ struct beep_sound *info = sndti_token(SOUND_BEEP, num);
+
+ /* only update if new state is not the same as old state */
+ if (info->enable == on)
+ return;
+
+ stream_update(info->stream);
+
+ info->enable = on;
+ /* restart wave from beginning */
+ info->incr = 0;
+ info->signal = 0x07fff;
+}
+
+
+
+/*************************************
+ *
+ * setting new frequency starts from beginning
+ *
+ *************************************/
+
+void beep_set_frequency(int num,int frequency)
+{
+ struct beep_sound *info = sndti_token(SOUND_BEEP, num);
+
+ if (info->frequency == frequency)
+ return;
+
+ stream_update(info->stream);
+ info->frequency = frequency;
+ info->signal = 0x07fff;
+ info->incr = 0;
+}
+
+
+
+/*************************************
+ *
+ * change a channel volume
+ *
+ *************************************/
+
+void beep_set_volume(int num, int volume)
+{
+ struct beep_sound *info = sndti_token(SOUND_BEEP, num);
+
+ stream_update(info->stream);
+
+ volume = 100 * volume / 7;
+
+ sndti_set_output_gain(SOUND_BEEP, num, 0, volume );
+}
+
+
+
+/**************************************************************************
+ * Generic get_info
+ **************************************************************************/
+
+static void beep_set_info(void *token, UINT32 state, sndinfo *info)
+{
+ switch (state)
+ {
+ /* no parameters to set */
+ }
+}
+
+
+void beep_get_info(void *token, UINT32 state, sndinfo *info)
+{
+ switch (state)
+ {
+ /* --- the following bits of info are returned as 64-bit signed integers --- */
+
+ /* --- the following bits of info are returned as pointers to data or functions --- */
+ case SNDINFO_PTR_SET_INFO: info->set_info = beep_set_info; break;
+ case SNDINFO_PTR_START: info->start = beep_start; break;
+ case SNDINFO_PTR_STOP: /* nothing */ break;
+ case SNDINFO_PTR_RESET: /* nothing */ break;
+
+ /* --- the following bits of info are returned as NULL-terminated strings --- */
+ case SNDINFO_STR_NAME: info->s = "Beep"; break;
+ case SNDINFO_STR_CORE_FAMILY: info->s = "Beep"; break;
+ case SNDINFO_STR_CORE_VERSION: info->s = "1.0"; break;
+ case SNDINFO_STR_CORE_FILE: info->s = __FILE__; break;
+ case SNDINFO_STR_CORE_CREDITS: info->s = "Copyright (c) 2005, The MESS Team"; break;
+ }
+}