centronics: Add SAMDAC device

scripts/src/bus.lua

@@ -2485,6 +2485,8 @@ if (BUSES["CENTRONICS"]~=null) then
 		MAME_DIR .. "src/devices/bus/centronics/printer.h",
 		MAME_DIR .. "src/devices/bus/centronics/digiblst.cpp",
 		MAME_DIR .. "src/devices/bus/centronics/digiblst.h",
+		MAME_DIR .. "src/devices/bus/centronics/samdac.cpp",
+		MAME_DIR .. "src/devices/bus/centronics/samdac.h",
 	}
 
 	dependency {

src/devices/bus/centronics/ctronics.cpp

@@ -134,6 +134,7 @@ device_centronics_peripheral_interface::~device_centronics_peripheral_interface(
 #include "printer.h"
 #include "covox.h"
 #include "chessmec.h"
+#include "samdac.h"
 
 void centronics_devices(device_slot_interface &device)
 {
@@ -147,4 +148,5 @@ void centronics_devices(device_slot_interface &device)
 	device.option_add("covox", CENTRONICS_COVOX);
 	device.option_add("covox_stereo", CENTRONICS_COVOX_STEREO);
 	device.option_add("chessmec", CENTRONICS_CHESSMEC);
+	device.option_add("samdac", CENTRONICS_SAMDAC);
 }

src/devices/bus/centronics/samdac.cpp

@@ -0,0 +1,99 @@
+// license: BSD-3-Clause
+// copyright-holders: Dirk Best
+/***************************************************************************
+
+    SAMDAC Stereo DAC for SAM Coupe
+
+***************************************************************************/
+
+#include "emu.h"
+#include "samdac.h"
+#include "sound/volt_reg.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], 0).add_route(ALL_OUTPUTS, "lspeaker", 0.5);
+	DAC_8BIT_R2R(config, m_dac[1], 0).add_route(ALL_OUTPUTS, "rspeaker", 0.5);
+
+	voltage_regulator_device &vref(VOLTAGE_REGULATOR(config, "vref"));
+	vref.add_route(0, m_dac[0], 1.0, DAC_VREF_POS_INPUT);
+	vref.add_route(0, m_dac[0], -1.0, DAC_VREF_NEG_INPUT);
+	vref.add_route(0, m_dac[1], 1.0, DAC_VREF_POS_INPUT);
+	vref.add_route(0, m_dac[1], -1.0, DAC_VREF_NEG_INPUT);
+}
+
+
+//**************************************************************************
+//  LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+//  centronics_samdac_device - constructor
+//-------------------------------------------------
+
+centronics_samdac_device::centronics_samdac_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t 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);
+	}
+}

src/devices/bus/centronics/samdac.h

@@ -0,0 +1,57 @@
+// license: BSD-3-Clause
+// copyright-holders: Dirk Best
+/***************************************************************************
+
+    SAMDAC Stereo DAC for SAM Coupe
+
+***************************************************************************/
+
+#ifndef MAME_BUS_CENTRONICS_SAMDAC_H
+#define MAME_BUS_CENTRONICS_SAMDAC_H
+
+#pragma once
+
+#include "ctronics.h"
+#include "sound/dac.h"
+
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+// ======================> centronics_samdac_device
+
+class centronics_samdac_device : public device_t, public device_centronics_peripheral_interface
+{
+public:
+	// construction/destruction
+	centronics_samdac_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+	// from centronics port
+	virtual DECLARE_WRITE_LINE_MEMBER( input_strobe ) override;
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data0 ) override { update_data(0, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data1 ) override { update_data(1, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data2 ) override { update_data(2, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data3 ) override { update_data(3, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data4 ) override { update_data(4, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data5 ) override { update_data(5, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data6 ) override { update_data(6, state); }
+	virtual DECLARE_WRITE_LINE_MEMBER( input_data7 ) override { update_data(7, state); }
+
+protected:
+	virtual void device_add_mconfig(machine_config &config) override;
+	virtual void device_start() override;
+
+private:
+	void update_data(int bit, int state);
+
+	required_device_array<dac_byte_interface, 2> m_dac;
+
+	int m_strobe;
+	uint8_t m_data[2];
+};
+
+// device type definition
+DECLARE_DEVICE_TYPE(CENTRONICS_SAMDAC, centronics_samdac_device)
+
+#endif // MAME_BUS_CENTRONICS_SAMDAC_H