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-rw-r--r--trunk/src/emu/sound/hc55516.c349
1 files changed, 349 insertions, 0 deletions
diff --git a/trunk/src/emu/sound/hc55516.c b/trunk/src/emu/sound/hc55516.c
new file mode 100644
index 00000000000..58d4d862886
--- /dev/null
+++ b/trunk/src/emu/sound/hc55516.c
@@ -0,0 +1,349 @@
+/*****************************************************************************
+
+ Harris HC-55516 (and related) emulator
+
+ Copyright Nicola Salmoria and the MAME Team
+
+*****************************************************************************/
+
+#include "emu.h"
+#include "hc55516.h"
+
+
+/* 4x oversampling */
+#define SAMPLE_RATE (48000 * 4)
+
+#define INTEGRATOR_LEAK_TC 0.001
+#define FILTER_DECAY_TC 0.004
+#define FILTER_CHARGE_TC 0.004
+#define FILTER_MIN 0.0416
+#define FILTER_MAX 1.0954
+#define SAMPLE_GAIN 10000.0
+
+
+typedef struct _hc55516_state hc55516_state;
+struct _hc55516_state
+{
+ sound_stream *channel;
+ int clock; /* 0 = software driven, non-0 = oscillator */
+ int active_clock_hi;
+ UINT8 shiftreg_mask;
+
+ UINT8 last_clock_state;
+ UINT8 digit;
+ UINT8 new_digit;
+ UINT8 shiftreg;
+
+ INT16 curr_sample;
+ INT16 next_sample;
+
+ UINT32 update_count;
+
+ double filter;
+ double integrator;
+};
+
+
+static double charge, decay, leak;
+
+
+static STREAM_UPDATE( hc55516_update );
+
+
+
+INLINE hc55516_state *get_safe_token(device_t *device)
+{
+ assert(device != NULL);
+ assert(device->type() == HC55516 ||
+ device->type() == MC3417 ||
+ device->type() == MC3418);
+ return (hc55516_state *)downcast<legacy_device_base *>(device)->token();
+}
+
+
+static void start_common(device_t *device, UINT8 _shiftreg_mask, int _active_clock_hi)
+{
+ hc55516_state *chip = get_safe_token(device);
+
+ /* compute the fixed charge, decay, and leak time constants */
+ charge = pow(exp(-1.0), 1.0 / (FILTER_CHARGE_TC * 16000.0));
+ decay = pow(exp(-1.0), 1.0 / (FILTER_DECAY_TC * 16000.0));
+ leak = pow(exp(-1.0), 1.0 / (INTEGRATOR_LEAK_TC * 16000.0));
+
+ chip->clock = device->clock();
+ chip->shiftreg_mask = _shiftreg_mask;
+ chip->active_clock_hi = _active_clock_hi;
+ chip->last_clock_state = 0;
+
+ /* create the stream */
+ chip->channel = device->machine().sound().stream_alloc(*device, 0, 1, SAMPLE_RATE, chip, hc55516_update);
+
+ device->save_item(NAME(chip->last_clock_state));
+ device->save_item(NAME(chip->digit));
+ device->save_item(NAME(chip->new_digit));
+ device->save_item(NAME(chip->shiftreg));
+ device->save_item(NAME(chip->curr_sample));
+ device->save_item(NAME(chip->next_sample));
+ device->save_item(NAME(chip->update_count));
+ device->save_item(NAME(chip->filter));
+ device->save_item(NAME(chip->integrator));
+}
+
+
+static DEVICE_START( hc55516 )
+{
+ start_common(device, 0x07, TRUE);
+}
+
+
+static DEVICE_START( mc3417 )
+{
+ start_common(device, 0x07, FALSE);
+}
+
+
+static DEVICE_START( mc3418 )
+{
+ start_common(device, 0x0f, FALSE);
+}
+
+
+
+static DEVICE_RESET( hc55516 )
+{
+ hc55516_state *chip = get_safe_token(device);
+ chip->last_clock_state = 0;
+}
+
+
+
+INLINE int is_external_osciallator(hc55516_state *chip)
+{
+ return chip->clock != 0;
+}
+
+
+INLINE int is_active_clock_transition(hc55516_state *chip, int clock_state)
+{
+ return (( chip->active_clock_hi && !chip->last_clock_state && clock_state) ||
+ (!chip->active_clock_hi && chip->last_clock_state && !clock_state));
+}
+
+
+INLINE int current_clock_state(hc55516_state *chip)
+{
+ return ((UINT64)chip->update_count * chip->clock * 2 / SAMPLE_RATE) & 0x01;
+}
+
+
+static void process_digit(hc55516_state *chip)
+{
+ double integrator = chip->integrator, temp;
+
+ /* shift the bit into the shift register */
+ chip->shiftreg = (chip->shiftreg << 1) | chip->digit;
+
+ /* move the estimator up or down a step based on the bit */
+ if (chip->digit)
+ integrator += chip->filter;
+ else
+ integrator -= chip->filter;
+
+ /* simulate leakage */
+ integrator *= leak;
+
+ /* if we got all 0's or all 1's in the last n bits, bump the step up */
+ if (((chip->shiftreg & chip->shiftreg_mask) == 0) ||
+ ((chip->shiftreg & chip->shiftreg_mask) == chip->shiftreg_mask))
+ {
+ chip->filter = FILTER_MAX - ((FILTER_MAX - chip->filter) * charge);
+
+ if (chip->filter > FILTER_MAX)
+ chip->filter = FILTER_MAX;
+ }
+
+ /* simulate decay */
+ else
+ {
+ chip->filter *= decay;
+
+ if (chip->filter < FILTER_MIN)
+ chip->filter = FILTER_MIN;
+ }
+
+ /* compute the sample as a 32-bit word */
+ temp = integrator * SAMPLE_GAIN;
+ chip->integrator = integrator;
+
+ /* compress the sample range to fit better in a 16-bit word */
+ if (temp < 0)
+ chip->next_sample = (int)(temp / (-temp * (1.0 / 32768.0) + 1.0));
+ else
+ chip->next_sample = (int)(temp / (temp * (1.0 / 32768.0) + 1.0));
+}
+
+
+static STREAM_UPDATE( hc55516_update )
+{
+ hc55516_state *chip = (hc55516_state *)param;
+ stream_sample_t *buffer = outputs[0];
+ int i;
+ INT32 sample, slope;
+
+ /* zero-length? bail */
+ if (samples == 0)
+ return;
+
+ if (!is_external_osciallator(chip))
+ {
+ /* track how many samples we've updated without a clock */
+ chip->update_count += samples;
+ if (chip->update_count > SAMPLE_RATE / 32)
+ {
+ chip->update_count = SAMPLE_RATE;
+ chip->next_sample = 0;
+ }
+ }
+
+ /* compute the interpolation slope */
+ sample = chip->curr_sample;
+ slope = ((INT32)chip->next_sample - sample) / samples;
+ chip->curr_sample = chip->next_sample;
+
+ if (is_external_osciallator(chip))
+ {
+ /* external oscillator */
+ for (i = 0; i < samples; i++, sample += slope)
+ {
+ UINT8 clock_state;
+
+ *buffer++ = sample;
+
+ chip->update_count++;
+
+ clock_state = current_clock_state(chip);
+
+ /* pull in next digit on the appropriate edge of the clock */
+ if (is_active_clock_transition(chip, clock_state))
+ {
+ chip->digit = chip->new_digit;
+
+ process_digit(chip);
+ }
+
+ chip->last_clock_state = clock_state;
+ }
+ }
+
+ /* software driven clock */
+ else
+ for (i = 0; i < samples; i++, sample += slope)
+ *buffer++ = sample;
+}
+
+
+void hc55516_clock_w(device_t *device, int state)
+{
+ hc55516_state *chip = get_safe_token(device);
+ UINT8 clock_state = state ? TRUE : FALSE;
+
+ /* only makes sense for setups with a software driven clock */
+ assert(!is_external_osciallator(chip));
+
+ /* speech clock changing? */
+ if (is_active_clock_transition(chip, clock_state))
+ {
+ /* update the output buffer before changing the registers */
+ chip->channel->update();
+
+ /* clear the update count */
+ chip->update_count = 0;
+
+ process_digit(chip);
+ }
+
+ /* update the clock */
+ chip->last_clock_state = clock_state;
+}
+
+
+void hc55516_digit_w(device_t *device, int digit)
+{
+ hc55516_state *chip = get_safe_token(device);
+
+ if (is_external_osciallator(chip))
+ {
+ chip->channel->update();
+ chip->new_digit = digit & 1;
+ }
+ else
+ chip->digit = digit & 1;
+}
+
+
+int hc55516_clock_state_r(device_t *device)
+{
+ hc55516_state *chip = get_safe_token(device);
+
+ /* only makes sense for setups with an external oscillator */
+ assert(is_external_osciallator(chip));
+
+ chip->channel->update();
+
+ return current_clock_state(chip);
+}
+
+
+
+/**************************************************************************
+ * Generic get_info
+ **************************************************************************/
+
+DEVICE_GET_INFO( hc55516 )
+{
+ switch (state)
+ {
+ /* --- the following bits of info are returned as 64-bit signed integers --- */
+ case DEVINFO_INT_TOKEN_BYTES: info->i = sizeof(hc55516_state); break;
+
+ /* --- the following bits of info are returned as pointers to data or functions --- */
+ case DEVINFO_FCT_START: info->start = DEVICE_START_NAME( hc55516 ); break;
+ case DEVINFO_FCT_RESET: info->reset = DEVICE_RESET_NAME( hc55516 ); break;
+
+ /* --- the following bits of info are returned as NULL-terminated strings --- */
+ case DEVINFO_STR_NAME: strcpy(info->s, "HC-55516"); break;
+ case DEVINFO_STR_FAMILY: strcpy(info->s, "CVSD"); break;
+ case DEVINFO_STR_VERSION: strcpy(info->s, "2.1"); break;
+ case DEVINFO_STR_SOURCE_FILE: strcpy(info->s, __FILE__); break;
+ case DEVINFO_STR_CREDITS: strcpy(info->s, "Copyright Nicola Salmoria and the MAME Team"); break;
+ }
+}
+
+
+DEVICE_GET_INFO( mc3417 )
+{
+ switch (state)
+ {
+ case DEVINFO_FCT_START: info->start = DEVICE_START_NAME( mc3417 ); break;
+ case DEVINFO_FCT_RESET: /* chip has no reset pin */ break;
+ case DEVINFO_STR_NAME: strcpy(info->s, "MC3417"); break;
+ default: DEVICE_GET_INFO_CALL(hc55516); break;
+ }
+}
+
+
+DEVICE_GET_INFO( mc3418 )
+{
+ switch (state)
+ {
+ case DEVINFO_FCT_START: info->start = DEVICE_START_NAME( mc3418 ); break;
+ case DEVINFO_FCT_RESET: /* chip has no reset pin */ break;
+ case DEVINFO_STR_NAME: strcpy(info->s, "MC3418"); break;
+ default: DEVICE_GET_INFO_CALL(hc55516); break;
+ }
+}
+
+
+DEFINE_LEGACY_SOUND_DEVICE(HC55516, hc55516);
+DEFINE_LEGACY_SOUND_DEVICE(MC3417, mc3417);
+DEFINE_LEGACY_SOUND_DEVICE(MC3418, mc3418);