diff options
Diffstat (limited to 'src/mame/audio/vc4000snd.c')
-rw-r--r-- | src/mame/audio/vc4000snd.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/src/mame/audio/vc4000snd.c b/src/mame/audio/vc4000snd.c new file mode 100644 index 00000000000..00b33d308ae --- /dev/null +++ b/src/mame/audio/vc4000snd.c @@ -0,0 +1,74 @@ +// license:GPL-2.0+ +// copyright-holders:Peter Trauner +/*************************************************************************** + + PeT mess@utanet.at + main part in video/ + +***************************************************************************/ + +#include "vc4000snd.h" + + +const device_type VC4000_SND = &device_creator<vc4000_sound_device>; + +vc4000_sound_device::vc4000_sound_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) + : device_t(mconfig, VC4000_SND, "Intertion Electronic VC 4000 Audio Custom", tag, owner, clock, "vc4000_sound", __FILE__), + device_sound_interface(mconfig, *this), + m_channel(NULL), + m_size(0), + m_pos(0), + m_level(0) +{ + memset(m_reg, 0, sizeof(UINT8)*1); +} + + +//------------------------------------------------- +// 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, stream_sample_t **inputs, stream_sample_t **outputs, int samples) +{ + int i; + stream_sample_t *buffer = outputs[0]; + + for (i = 0; i < samples; i++, buffer++) + { + *buffer = 0; + if (m_reg[0] && m_pos <= m_size / 2) + { + *buffer = 0x7fff; + } + 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; + } +} |