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// license:BSD-3-Clause
// copyright-holders:Aaron Giles
/***************************************************************************
dac.h
DAC device emulator.
***************************************************************************/
#ifndef __DAC_H__
#define __DAC_H__
//**************************************************************************
// INTERFACE CONFIGURATION MACROS
//**************************************************************************
#define MCFG_DAC_ADD(_tag) \
MCFG_DEVICE_ADD(_tag, DAC, 0)
//**************************************************************************
// TYPE DEFINITIONS
//**************************************************************************
// ======================> dac_device
class dac_device : public device_t,
public device_sound_interface
{
// default to 4x oversampling
static const UINT32 DEFAULT_SAMPLE_RATE = 48000 * 4;
public:
// construction/destruction
dac_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
// public interface
INT16 output() const { return m_output; }
void write(INT16 data) { m_stream->update(); m_output = data; }
void write_unsigned8(UINT8 data) { write(data * 32767 / 255); } // 0..255, mapped to 0..32767
void write_signed8(UINT8 data) { write((data - 0x80) * 32767 / 128); } // 0..255, mapped to -32767..32767
void write_unsigned16(UINT16 data) { write(data / 2); } // 0..65535, mapped to 0..32767
void write_signed16(UINT16 data) { write(data - 0x8000); } // 0..65535, mapped to -32768..32767
// wrappers
DECLARE_WRITE8_MEMBER( write_unsigned8 );
DECLARE_WRITE8_MEMBER( write_signed8 );
protected:
// device-level overrides
virtual void device_start();
virtual void device_reset();
// device_sound_interface overrides
virtual void sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples);
// internal state
sound_stream * m_stream;
INT16 m_output;
};
// device type definition
extern const device_type DAC;
#endif /* __DAC_H__ */
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