//WRITE8_MEMBER( ay8910_device::data_w )
public void ay8910_device_address_data_w_ay2(address_space space, offs_t offset, u8 data, u8 mem_mask = 0xff)
{
ay8910_device device = (ay8910_device)subdevice("ay2");
device.data_w(space, offset, data, mem_mask);
}
// device_sound_interface overrides
//-------------------------------------------------
// sound_stream_update - handle a stream update
//-------------------------------------------------
public override void sound_stream_update(sound_stream stream, ListPointer <stream_sample_t> [] inputs, ListPointer <stream_sample_t> [] outputs, int samples)
{
ay8910_device ay8910 = (ay8910_device)device();
ListPointer <stream_sample_t> [] buf = new ListPointer <stream_sample_t> [ay8910_device.NUM_CHANNELS]; //stream_sample_t *buf[NUM_CHANNELS];
int chan;
buf[0] = new ListPointer <stream_sample_t>(outputs[0]);
buf[1] = null;
buf[2] = null;
if (ay8910.m_streams == ay8910_device.NUM_CHANNELS)
{
buf[1] = outputs[1];
buf[2] = outputs[2];
}
/* hack to prevent us from hanging when starting filtered outputs */
if (ay8910.m_ready == 0)
{
for (chan = 0; chan < ay8910_device.NUM_CHANNELS; chan++)
{
if (buf[chan] != null)
{
memset(buf[chan], 0, (UInt32)samples); //memset(buf[chan], 0, samples * sizeof_(*buf[chan]));
}
}
}
/* The 8910 has three outputs, each output is the mix of one of the three */
/* tone generators and of the (single) noise generator. The two are mixed */
/* BEFORE going into the DAC. The formula to mix each channel is: */
/* (ToneOn | ToneDisable) & (NoiseOn | NoiseDisable). */
/* Note that this means that if both tone and noise are disabled, the output */
/* is 1, not 0, and can be modulated changing the volume. */
/* buffering loop */
while (samples != 0)
{
for (chan = 0; chan < ay8910_device.NUM_CHANNELS; chan++)
{
ay8910.m_count[chan]++;
if (ay8910.m_count[chan] >= ay8910.TONE_PERIOD(chan))
{
ay8910.m_output[chan] ^= 1;
ay8910.m_count[chan] = 0;
}
}
ay8910.m_count_noise++;
if (ay8910.m_count_noise >= ay8910.NOISE_PERIOD())
{
/* toggle the prescaler output. Noise is no different to
* channels.
*/
ay8910.m_count_noise = 0;
ay8910.m_prescale_noise ^= 1;
if (ay8910.m_prescale_noise != 0)
{
/* The Random Number Generator of the 8910 is a 17-bit shift */
/* register. The input to the shift register is bit0 XOR bit3 */
/* (bit0 is the output). This was verified on AY-3-8910 and YM2149 chips. */
ay8910.m_rng ^= (((ay8910.m_rng & 1) ^ ((ay8910.m_rng >> 3) & 1)) << 17);
ay8910.m_rng >>= 1;
}
}
for (chan = 0; chan < ay8910_device.NUM_CHANNELS; chan++)
{
ay8910.m_vol_enabled[chan] = (byte)((ay8910.m_output[chan] | ay8910.TONE_ENABLEQ(chan)) & (ay8910.NOISE_OUTPUT() | ay8910.NOISE_ENABLEQ(chan)));
}
/* update envelope */
if (ay8910.m_holding == 0)
{
ay8910.m_count_env++;
if (ay8910.m_count_env >= ay8910.ENVELOPE_PERIOD() * ay8910.m_step)
{
ay8910.m_count_env = 0;
ay8910.m_env_step--;
/* check envelope current position */
if (ay8910.m_env_step < 0)
{
if (ay8910.m_hold != 0)
{
if (ay8910.m_alternate != 0)
{
ay8910.m_attack ^= ay8910.m_env_step_mask;
}
ay8910.m_holding = 1;
ay8910.m_env_step = 0;
}
else
{
/* if CountEnv has looped an odd number of times (usually 1), */
/* invert the output. */
if (ay8910.m_alternate != 0 && (ay8910.m_env_step & (ay8910.m_env_step_mask + 1)) != 0)
{
ay8910.m_attack ^= ay8910.m_env_step_mask;
}
ay8910.m_env_step &= (sbyte)ay8910.m_env_step_mask;
}
}
}
}
ay8910.m_env_volume = (UInt32)(ay8910.m_env_step ^ ay8910.m_attack);
if (ay8910.m_streams == 3)
{
for (chan = 0; chan < ay8910_device.NUM_CHANNELS; chan++)
{
if (ay8910.TONE_ENVELOPE(chan) != 0)
{
if (ay8910.type() == ay8914_device.AY8914) // AY8914 Has a two bit tone_envelope field
{
buf[chan][0] = ay8910.m_env_table[chan, ay8910.m_vol_enabled[chan] != 0 ? ay8910.m_env_volume >> (3 - ay8910.TONE_ENVELOPE(chan)) : 0]; // *(buf[chan]++)
buf[chan]++;
}
else
{
buf[chan][0] = ay8910.m_env_table[chan, ay8910.m_vol_enabled[chan] != 0 ? ay8910.m_env_volume : 0]; // *(buf[chan]++)
buf[chan]++;
}
}
else
{
buf[chan][0] = ay8910.m_vol_table[chan, ay8910.m_vol_enabled[chan] != 0 ? ay8910.TONE_VOLUME(chan) : 0]; // *(buf[chan]++)
buf[chan]++;
}
}
}
else
{
buf[0][0] = ay8910.mix_3D(); // *(buf[0]++)
buf[0]++;
}
samples--;
}
}
