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-rw-r--r--src/mame/audio/meadows.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/src/mame/audio/meadows.c b/src/mame/audio/meadows.c
new file mode 100644
index 00000000000..c6616eb2fd6
--- /dev/null
+++ b/src/mame/audio/meadows.c
@@ -0,0 +1,125 @@
+/***************************************************************************
+ meadows.c
+ Sound handler
+ Dead Eye, Gypsy Juggler
+
+ J. Buchmueller, June '98
+****************************************************************************/
+
+#include "driver.h"
+#include "cpu/s2650/s2650.h"
+#include "meadows.h"
+#include "sound/samples.h"
+#include "sound/dac.h"
+
+
+UINT8 meadows_0c00 = 0;
+UINT8 meadows_0c01 = 0;
+UINT8 meadows_0c02 = 0;
+UINT8 meadows_0c03 = 0;
+static UINT8 meadows_dac = 0;
+static int dac_enable;
+
+#define BASE_CLOCK 5000000
+#define BASE_CTR1 (BASE_CLOCK / 256)
+#define BASE_CTR2 (BASE_CLOCK / 32)
+
+#define DIV2OR4_CTR2 0x01
+#define ENABLE_CTR2 0x02
+#define ENABLE_DAC 0x04
+#define ENABLE_CTR1 0x08
+
+static int channel;
+static int freq1 = 1000;
+static int freq2 = 1000;
+static INT16 waveform[2] = { -120*256, 120*256 };
+
+/************************************/
+/* Sound handler start */
+/************************************/
+void meadows_sh_start(void)
+{
+ int vol[2];
+
+ vol[0]=vol[1]=255;
+
+ sample_set_volume(0,0);
+ sample_start_raw(0,waveform,sizeof(waveform)/2,freq1,1);
+ sample_set_volume(1,0);
+ sample_start_raw(1,waveform,sizeof(waveform)/2,freq2,1);
+}
+
+/************************************/
+/* Sound handler update */
+/************************************/
+void meadows_sh_update(void)
+{
+static UINT8 latched_0c01 = 0;
+static UINT8 latched_0c02 = 0;
+static UINT8 latched_0c03 = 0;
+int preset, amp;
+
+ if (latched_0c01 != meadows_0c01 || latched_0c03 != meadows_0c03)
+ {
+ /* amplitude is a combination of the upper 4 bits of 0c01 */
+ /* and bit 4 merged from S2650's flag output */
+ amp = ((meadows_0c03 & ENABLE_CTR1) == 0) ? 0 : (meadows_0c01 & 0xf0) >> 1;
+ if( activecpu_get_reg(S2650_FO) )
+ amp += 0x80;
+ /* calculate frequency for counter #1 */
+ /* bit 0..3 of 0c01 are ctr preset */
+ preset = (meadows_0c01 & 15) ^ 15;
+ if (preset)
+ freq1 = BASE_CTR1 / (preset + 1);
+ else amp = 0;
+ logerror("meadows ctr1 channel #%d preset:%3d freq:%5d amp:%d\n", channel, preset, freq1, amp);
+ sample_set_freq(0, freq1 * sizeof(waveform)/2);
+ sample_set_volume(0,amp/255.0);
+ }
+
+ if (latched_0c02 != meadows_0c02 || latched_0c03 != meadows_0c03)
+ {
+ /* calculate frequency for counter #2 */
+ /* 0c02 is ctr preset, 0c03 bit 0 enables division by 2 */
+ amp = ((meadows_0c03 & ENABLE_CTR2) != 0) ? 0xa0 : 0;
+ preset = meadows_0c02 ^ 0xff;
+ if (preset)
+ {
+ freq2 = BASE_CTR2 / (preset + 1) / 2;
+ if ((meadows_0c03 & DIV2OR4_CTR2) == 0)
+ freq2 >>= 1;
+ }
+ else amp = 0;
+ logerror("meadows ctr2 channel #%d preset:%3d freq:%5d amp:%d\n", channel+1, preset, freq2, amp);
+ sample_set_freq(1, freq2 * sizeof(waveform));
+ sample_set_volume(1,amp/255.0);
+ }
+
+ if (latched_0c03 != meadows_0c03)
+ {
+ dac_enable = meadows_0c03 & ENABLE_DAC;
+
+ if (dac_enable)
+ DAC_data_w(0, meadows_dac);
+ else
+ DAC_data_w(0, 0);
+ }
+
+ latched_0c01 = meadows_0c01;
+ latched_0c02 = meadows_0c02;
+ latched_0c03 = meadows_0c03;
+}
+
+/************************************/
+/* Write DAC value */
+/************************************/
+void meadows_sh_dac_w(int data)
+{
+ meadows_dac = data;
+ if (dac_enable)
+ DAC_data_w(0, meadows_dac);
+ else
+ DAC_data_w(0, 0);
+}
+
+