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// license: BSD-3-Clause
// copyright-holders: Dirk Best
/***************************************************************************
SAMDAC Stereo DAC for SAM Coupe
***************************************************************************/
#include "emu.h"
#include "samdac.h"
#include "speaker.h"
//**************************************************************************
// DEVICE DEFINITIONS
//**************************************************************************
DEFINE_DEVICE_TYPE(CENTRONICS_SAMDAC, centronics_samdac_device, "centronics_samdac", "SAMDAC")
//-------------------------------------------------
// device_add_mconfig - add device configuration
//-------------------------------------------------
void centronics_samdac_device::device_add_mconfig(machine_config &config)
{
SPEAKER(config, "lspeaker").front_left();
SPEAKER(config, "rspeaker").front_right();
DAC_8BIT_R2R(config, m_dac[0]).add_route(ALL_OUTPUTS, "lspeaker", 0.5);
DAC_8BIT_R2R(config, m_dac[1]).add_route(ALL_OUTPUTS, "rspeaker", 0.5);
}
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
//-------------------------------------------------
// centronics_samdac_device - constructor
//-------------------------------------------------
centronics_samdac_device::centronics_samdac_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock) :
device_t(mconfig, CENTRONICS_SAMDAC, tag, owner, clock),
device_centronics_peripheral_interface(mconfig, *this),
m_dac(*this, "dac%u", 0U),
m_strobe(0),
m_data{ 0x00, 0x00 }
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void centronics_samdac_device::device_start()
{
// register for savestates
save_item(NAME(m_strobe));
save_item(NAME(m_data), 2);
}
//**************************************************************************
// IMPLEMENTATION
//**************************************************************************
WRITE_LINE_MEMBER( centronics_samdac_device::input_strobe )
{
// raising edge, write to left channel
if (m_strobe == 0 && state == 1)
m_dac[0]->data_w(m_data[0]);
// failing edge, write to right channel
if (m_strobe == 1 && state == 0)
m_dac[1]->data_w(m_data[1]);
m_strobe = state;
}
void centronics_samdac_device::update_data(int bit, int state)
{
if (state)
{
m_data[0] |= (1 << bit);
m_data[1] |= (1 << bit);
}
else
{
m_data[0] &= ~(1 << bit);
m_data[1] &= ~(1 << bit);
}
}
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