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-rw-r--r--src/mame/audio/polyplay.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/src/mame/audio/polyplay.c b/src/mame/audio/polyplay.c
new file mode 100644
index 00000000000..edaa1a812a4
--- /dev/null
+++ b/src/mame/audio/polyplay.c
@@ -0,0 +1,72 @@
+/***************************************************************************
+
+ Poly-Play
+ (c) 1985 by VEB Polytechnik Karl-Marx-Stadt
+
+ sound hardware
+
+ driver written by Martin Buchholz (buchholz@mail.uni-greifswald.de)
+
+***************************************************************************/
+#include "driver.h"
+#include <math.h>
+#include "sound/samples.h"
+
+#define LFO_VOLUME 25
+#define SAMPLE_LENGTH 32
+#define SAMPLE_AMPLITUDE 0x4000
+
+static int freq1, freq2, channel_playing1, channel_playing2;
+
+static INT16 backgroundwave[SAMPLE_LENGTH];
+
+void polyplay_sh_start(void)
+{
+ int i;
+
+ for (i = 0; i < SAMPLE_LENGTH / 2; i++) {
+ backgroundwave[i] = + SAMPLE_AMPLITUDE;
+ }
+ for (i = SAMPLE_LENGTH / 2; i < SAMPLE_LENGTH; i++) {
+ backgroundwave[i] = - SAMPLE_AMPLITUDE;
+ }
+ freq1 = freq2 = 110;
+ channel_playing1 = 0;
+ channel_playing2 = 0;
+}
+
+void polyplay_set_channel1(int active)
+{
+ channel_playing1 = active;
+}
+
+void polyplay_set_channel2(int active)
+{
+ channel_playing2 = active;
+}
+
+void polyplay_play_channel1(int data)
+{
+ if (data) {
+ freq1 = 2457600 / 16 / data / 8;
+ sample_set_volume(0, channel_playing1 * 1.0);
+ sample_start_raw(0, backgroundwave, sizeof(backgroundwave)/2, sizeof(backgroundwave)*freq1,1);
+ }
+ else {
+ sample_stop(0);
+ sample_stop(1);
+ }
+}
+
+void polyplay_play_channel2(int data)
+{
+ if (data) {
+ freq2 = 2457600 / 16 / data / 8;
+ sample_set_volume(1, channel_playing2 * 1.0);
+ sample_start_raw(1, backgroundwave, sizeof(backgroundwave)/2, sizeof(backgroundwave)*freq2,1);
+ }
+ else {
+ sample_stop(0);
+ sample_stop(1);
+ }
+}