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-rw-r--r--trunk/src/emu/sound/okim6258.c384
1 files changed, 384 insertions, 0 deletions
diff --git a/trunk/src/emu/sound/okim6258.c b/trunk/src/emu/sound/okim6258.c
new file mode 100644
index 00000000000..aa939cc3fe2
--- /dev/null
+++ b/trunk/src/emu/sound/okim6258.c
@@ -0,0 +1,384 @@
+/**********************************************************************************************
+ *
+ * OKI MSM6258 ADPCM
+ *
+ * TODO:
+ * 3-bit ADPCM support
+ * Recording?
+ *
+ **********************************************************************************************/
+
+
+#include "emu.h"
+#include "okim6258.h"
+
+#define COMMAND_STOP (1 << 0)
+#define COMMAND_PLAY (1 << 1)
+#define COMMAND_RECORD (1 << 2)
+
+#define STATUS_PLAYING (1 << 1)
+#define STATUS_RECORDING (1 << 2)
+
+static const int dividers[4] = { 1024, 768, 512, 512 };
+
+typedef struct _okim6258_state okim6258_state;
+struct _okim6258_state
+{
+ UINT8 status;
+
+ UINT32 master_clock; /* master clock frequency */
+ UINT32 divider; /* master clock divider */
+ UINT8 adpcm_type; /* 3/4 bit ADPCM select */
+ UINT8 data_in; /* ADPCM data-in register */
+ UINT8 nibble_shift; /* nibble select */
+ sound_stream *stream; /* which stream are we playing on? */
+
+ UINT8 output_bits;
+
+ INT32 signal;
+ INT32 step;
+};
+
+/* step size index shift table */
+static const int index_shift[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
+
+/* lookup table for the precomputed difference */
+static int diff_lookup[49*16];
+
+/* tables computed? */
+static int tables_computed = 0;
+
+INLINE okim6258_state *get_safe_token(device_t *device)
+{
+ assert(device != NULL);
+ assert(device->type() == OKIM6258);
+ return (okim6258_state *)downcast<legacy_device_base *>(device)->token();
+}
+
+/**********************************************************************************************
+
+ compute_tables -- compute the difference tables
+
+***********************************************************************************************/
+
+static void compute_tables(void)
+{
+ /* nibble to bit map */
+ static const int nbl2bit[16][4] =
+ {
+ { 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},
+ {-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}
+ };
+
+ int step, nib;
+
+ /* loop over all possible steps */
+ for (step = 0; step <= 48; step++)
+ {
+ /* compute the step value */
+ int stepval = floor(16.0 * pow(11.0 / 10.0, (double)step));
+
+ /* loop over all nibbles and compute the difference */
+ for (nib = 0; nib < 16; nib++)
+ {
+ diff_lookup[step*16 + nib] = nbl2bit[nib][0] *
+ (stepval * nbl2bit[nib][1] +
+ stepval/2 * nbl2bit[nib][2] +
+ stepval/4 * nbl2bit[nib][3] +
+ stepval/8);
+ }
+ }
+
+ tables_computed = 1;
+}
+
+
+static INT16 clock_adpcm(okim6258_state *chip, UINT8 nibble)
+{
+ INT32 max = (1 << (chip->output_bits - 1)) - 1;
+ INT32 min = -(1 << (chip->output_bits - 1));
+
+ chip->signal += diff_lookup[chip->step * 16 + (nibble & 15)];
+
+ /* clamp to the maximum */
+ if (chip->signal > max)
+ chip->signal = max;
+ else if (chip->signal < min)
+ chip->signal = min;
+
+ /* adjust the step size and clamp */
+ chip->step += index_shift[nibble & 7];
+ if (chip->step > 48)
+ chip->step = 48;
+ else if (chip->step < 0)
+ chip->step = 0;
+
+ /* return the signal scaled up to 32767 */
+ return chip->signal << 4;
+}
+
+/**********************************************************************************************
+
+ okim6258_update -- update the sound chip so that it is in sync with CPU execution
+
+***********************************************************************************************/
+
+static STREAM_UPDATE( okim6258_update )
+{
+ okim6258_state *chip = (okim6258_state *)param;
+ stream_sample_t *buffer = outputs[0];
+
+ memset(outputs[0], 0, samples * sizeof(*outputs[0]));
+
+ if (chip->status & STATUS_PLAYING)
+ {
+ int nibble_shift = chip->nibble_shift;
+
+ while (samples)
+ {
+ /* Compute the new amplitude and update the current step */
+ int nibble = (chip->data_in >> nibble_shift) & 0xf;
+
+ /* Output to the buffer */
+ INT16 sample = clock_adpcm(chip, nibble);
+
+ nibble_shift ^= 4;
+
+ *buffer++ = sample;
+ samples--;
+ }
+
+ /* Update the parameters */
+ chip->nibble_shift = nibble_shift;
+ }
+ else
+ {
+ /* Fill with 0 */
+ while (samples--)
+ *buffer++ = 0;
+ }
+}
+
+
+
+/**********************************************************************************************
+
+ state save support for MAME
+
+***********************************************************************************************/
+
+static void okim6258_state_save_register(okim6258_state *info, device_t *device)
+{
+ device->save_item(NAME(info->status));
+ device->save_item(NAME(info->master_clock));
+ device->save_item(NAME(info->divider));
+ device->save_item(NAME(info->data_in));
+ device->save_item(NAME(info->nibble_shift));
+ device->save_item(NAME(info->signal));
+ device->save_item(NAME(info->step));
+}
+
+
+/**********************************************************************************************
+
+ OKIM6258_start -- start emulation of an OKIM6258-compatible chip
+
+***********************************************************************************************/
+
+static DEVICE_START( okim6258 )
+{
+ const okim6258_interface *intf = (const okim6258_interface *)device->static_config();
+ okim6258_state *info = get_safe_token(device);
+
+ compute_tables();
+
+ info->master_clock = device->clock();
+ info->adpcm_type = intf->adpcm_type;
+
+ /* D/A precision is 10-bits but 12-bit data can be output serially to an external DAC */
+ info->output_bits = intf->output_12bits ? 12 : 10;
+ info->divider = dividers[intf->divider];
+
+ info->stream = device->machine().sound().stream_alloc(*device, 0, 1, device->clock()/info->divider, info, okim6258_update);
+
+ info->signal = -2;
+ info->step = 0;
+
+ okim6258_state_save_register(info, device);
+}
+
+
+/**********************************************************************************************
+
+ OKIM6258_stop -- stop emulation of an OKIM6258-compatible chip
+
+***********************************************************************************************/
+
+static DEVICE_RESET( okim6258 )
+{
+ okim6258_state *info = get_safe_token(device);
+
+ info->stream->update();
+
+ info->signal = -2;
+ info->step = 0;
+ info->status = 0;
+}
+
+
+/**********************************************************************************************
+
+ okim6258_set_divider -- set the master clock divider
+
+***********************************************************************************************/
+
+void okim6258_set_divider(device_t *device, int val)
+{
+ okim6258_state *info = get_safe_token(device);
+ int divider = dividers[val];
+
+ info->divider = dividers[val];
+ info->stream->set_sample_rate(info->master_clock / divider);
+}
+
+
+/**********************************************************************************************
+
+ okim6258_set_clock -- set the master clock
+
+***********************************************************************************************/
+
+void okim6258_set_clock(device_t *device, int val)
+{
+ okim6258_state *info = get_safe_token(device);
+
+ info->master_clock = val;
+ info->stream->set_sample_rate(info->master_clock / info->divider);
+}
+
+
+/**********************************************************************************************
+
+ okim6258_get_vclk -- get the VCLK/sampling frequency
+
+***********************************************************************************************/
+
+int okim6258_get_vclk(device_t *device)
+{
+ okim6258_state *info = get_safe_token(device);
+
+ return (info->master_clock / info->divider);
+}
+
+
+/**********************************************************************************************
+
+ okim6258_status_r -- read the status port of an OKIM6258-compatible chip
+
+***********************************************************************************************/
+
+READ8_DEVICE_HANDLER( okim6258_status_r )
+{
+ okim6258_state *info = get_safe_token(device);
+
+ info->stream->update();
+
+ return (info->status & STATUS_PLAYING) ? 0x00 : 0x80;
+}
+
+
+/**********************************************************************************************
+
+ okim6258_data_w -- write to the control port of an OKIM6258-compatible chip
+
+***********************************************************************************************/
+WRITE8_DEVICE_HANDLER( okim6258_data_w )
+{
+ okim6258_state *info = get_safe_token(device);
+
+ /* update the stream */
+ info->stream->update();
+
+ info->data_in = data;
+ info->nibble_shift = 0;
+}
+
+
+/**********************************************************************************************
+
+ okim6258_ctrl_w -- write to the control port of an OKIM6258-compatible chip
+
+***********************************************************************************************/
+
+WRITE8_DEVICE_HANDLER( okim6258_ctrl_w )
+{
+ okim6258_state *info = get_safe_token(device);
+
+ info->stream->update();
+
+ if (data & COMMAND_STOP)
+ {
+ info->status &= ~(STATUS_PLAYING | STATUS_RECORDING);
+ return;
+ }
+
+ if (data & COMMAND_PLAY)
+ {
+ if (!(info->status & STATUS_PLAYING))
+ {
+ info->status |= STATUS_PLAYING;
+
+ /* Also reset the ADPCM parameters */
+ info->signal = -2;
+ info->step = 0;
+ info->nibble_shift = 0;
+ }
+ }
+ else
+ {
+ info->status &= ~STATUS_PLAYING;
+ }
+
+ if (data & COMMAND_RECORD)
+ {
+ logerror("M6258: Record enabled\n");
+ info->status |= STATUS_RECORDING;
+ }
+ else
+ {
+ info->status &= ~STATUS_RECORDING;
+ }
+}
+
+
+
+
+/**************************************************************************
+ * Generic get_info
+ **************************************************************************/
+
+DEVICE_GET_INFO( okim6258 )
+{
+ switch (state)
+ {
+ /* --- the following bits of info are returned as 64-bit signed integers --- */
+ case DEVINFO_INT_TOKEN_BYTES: info->i = sizeof(okim6258_state); break;
+
+ /* --- the following bits of info are returned as pointers to data or functions --- */
+ case DEVINFO_FCT_START: info->start = DEVICE_START_NAME(okim6258); break;
+ case DEVINFO_FCT_STOP: /* nothing */ break;
+ case DEVINFO_FCT_RESET: info->reset = DEVICE_RESET_NAME(okim6258); break;
+
+ /* --- the following bits of info are returned as NULL-terminated strings --- */
+ case DEVINFO_STR_NAME: strcpy(info->s, "OKI6258"); break;
+ case DEVINFO_STR_FAMILY: strcpy(info->s, "OKI ADPCM"); break;
+ case DEVINFO_STR_VERSION: strcpy(info->s, "1.0"); 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;
+ }
+}
+
+
+DEFINE_LEGACY_SOUND_DEVICE(OKIM6258, okim6258);