// license:GPL-2.0+
// copyright-holders:Peter Trauner
/***************************************************************************
PeT mess@utanet.at
main part in video/
***************************************************************************/
#include "emu.h"
#include "vc4000.h"
DEFINE_DEVICE_TYPE(VC4000_SND, vc4000_sound_device, "vc4000_sound", "Interton Electronic VC 4000 Custom Sound")
vc4000_sound_device::vc4000_sound_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, VC4000_SND, tag, owner, clock)
, device_sound_interface(mconfig, *this)
, m_channel(nullptr)
, m_reg{ 0 }
, m_size(0)
, m_pos(0)
, m_level(0)
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void vc4000_sound_device::device_start()
{
m_channel = stream_alloc(0, 1, machine().sample_rate());
}
//-------------------------------------------------
// sound_stream_update - handle a stream update
//-------------------------------------------------
void vc4000_sound_device::sound_stream_update(sound_stream &stream, std::vector<read_stream_view> const &inputs, std::vector<write_stream_view> &outputs)
{
int i;
auto &buffer = outputs[0];
for (i = 0; i < buffer.samples(); i++)
{
buffer.put(i, (m_reg[0] && m_pos <= m_size / 2) ? 1.0 : 0.0);
if (m_pos <= m_size)
m_pos++;
if (m_pos > m_size)
m_pos = 0;
}
}
void vc4000_sound_device::soundport_w(int offset, int data)
{
m_channel->update();
m_reg[offset] = data;
switch (offset)
{
case 0:
m_pos = 0;
m_level = true;
// frequency 7874/(data+1)
m_size = machine().sample_rate() * (data + 1) /7874;
break;
}
}