bus/electron: Added the P.R.E.S. AP1/AP6 and First Byte Printer Interface devices.

scripts/src/bus.lua

@@ -1025,6 +1025,8 @@ if (BUSES["ELECTRON"]~=null) then
 		MAME_DIR .. "src/devices/bus/electron/exp.h",
 		MAME_DIR .. "src/devices/bus/electron/fbjoy.cpp",
 		MAME_DIR .. "src/devices/bus/electron/fbjoy.h",
+		MAME_DIR .. "src/devices/bus/electron/fbprint.cpp",
+		MAME_DIR .. "src/devices/bus/electron/fbprint.h",
 		MAME_DIR .. "src/devices/bus/electron/mode7.cpp",
 		MAME_DIR .. "src/devices/bus/electron/mode7.h",
 		MAME_DIR .. "src/devices/bus/electron/plus1.cpp",

src/devices/bus/electron/exp.cpp

@@ -107,7 +107,7 @@ void electron_expansion_slot_device::expbus_w(offs_t offset, uint8_t data)
 
 // slot devices
 #include "fbjoy.h"
-//#include "fbprint.h"
+#include "fbprint.h"
 #include "mode7.h"
 //#include "lebox.h"
 #include "plus1.h"
@@ -123,8 +123,10 @@ void electron_expansion_slot_device::expbus_w(offs_t offset, uint8_t data)
 
 void electron_expansion_devices(device_slot_interface &device)
 {
+	device.option_add("ap1", ELECTRON_AP1);
+	device.option_add("ap6", ELECTRON_AP6);
 	device.option_add("fbjoy", ELECTRON_FBJOY);
-	//device.option_add("fbprint", ELECTRON_FBPRINT);
+	device.option_add("fbprint", ELECTRON_FBPRINT);
 	device.option_add("mode7", ELECTRON_MODE7);
 	//device.option_add("lebox", ELECTRON_LEBOX);
 	device.option_add("plus1", ELECTRON_PLUS1);

src/devices/bus/electron/fbprint.cpp

@@ -0,0 +1,90 @@
+// license:BSD-3-Clause
+// copyright-holders:Nigel Barnes
+/**********************************************************************
+
+    First Byte Printer Interface
+
+**********************************************************************/
+
+
+#include "emu.h"
+#include "fbprint.h"
+
+
+//**************************************************************************
+//  DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(ELECTRON_FBPRINT, electron_fbprint_device, "electron_fbprint", "First Byte Printer Interface")
+
+
+//-------------------------------------------------
+//  device_add_mconfig - add device configuration
+//-------------------------------------------------
+
+void electron_fbprint_device::device_add_mconfig(machine_config &config)
+{
+	/* printer */
+	CENTRONICS(config, m_centronics, centronics_devices, "printer");
+	m_centronics->busy_handler().set([this](int state) { m_centronics_busy = state; });
+	output_latch_device &latch(OUTPUT_LATCH(config, "cent_data_out"));
+	m_centronics->set_output_latch(latch);
+}
+
+//**************************************************************************
+//  LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+//  electron_fbprint_device - constructor
+//-------------------------------------------------
+
+electron_fbprint_device::electron_fbprint_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+	: device_t(mconfig, ELECTRON_FBPRINT, tag, owner, clock)
+	, device_electron_expansion_interface(mconfig, *this)
+	, m_centronics(*this, "centronics")
+	, m_cent_data_out(*this, "cent_data_out")
+	, m_centronics_busy(0)
+{
+}
+
+
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void electron_fbprint_device::device_start()
+{
+}
+
+
+//-------------------------------------------------
+//  expbus_r - expansion data read
+//-------------------------------------------------
+
+uint8_t electron_fbprint_device::expbus_r(offs_t offset)
+{
+	uint8_t data = 0xff;
+
+	if (offset == 0xfc72)
+	{
+		data = (m_centronics_busy << 7) | 0x7f;
+	}
+
+	return data;
+}
+
+
+//-------------------------------------------------
+//  expbus_w - expansion data write
+//-------------------------------------------------
+
+void electron_fbprint_device::expbus_w(offs_t offset, uint8_t data)
+{
+	if (offset == 0xfc71)
+	{
+		m_cent_data_out->write(data);
+		m_centronics->write_strobe(0);
+		m_centronics->write_strobe(1);
+	}
+}

src/devices/bus/electron/fbprint.h

@@ -0,0 +1,50 @@
+// license:BSD-3-Clause
+// copyright-holders:Nigel Barnes
+/**********************************************************************
+
+    First Byte Printer Interface
+
+**********************************************************************/
+
+
+#ifndef MAME_BUS_ELECTRON_FBPRINT_H
+#define MAME_BUS_ELECTRON_FBPRINT_H
+
+#include "exp.h"
+#include "bus/centronics/ctronics.h"
+
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+class electron_fbprint_device:
+	public device_t,
+	public device_electron_expansion_interface
+{
+public:
+	// construction/destruction
+	electron_fbprint_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+protected:
+	// device-level overrides
+	virtual void device_start() override;
+
+	// optional information overrides
+	virtual void device_add_mconfig(machine_config &config) override;
+
+	virtual uint8_t expbus_r(offs_t offset) override;
+	virtual void expbus_w(offs_t offset, uint8_t data) override;
+
+	required_device<centronics_device> m_centronics;
+	required_device<output_latch_device> m_cent_data_out;
+
+	int m_centronics_busy;
+};
+
+
+// device type definition
+DECLARE_DEVICE_TYPE(ELECTRON_FBPRINT, electron_fbprint_device)
+
+
+#endif /* MAME_BUS_ELECTRON_FBPRINT_H */

src/devices/bus/electron/plus1.cpp

@@ -23,6 +23,8 @@
 //**************************************************************************
 
 DEFINE_DEVICE_TYPE(ELECTRON_PLUS1, electron_plus1_device, "electron_plus1", "Acorn Plus 1 Expansion")
+DEFINE_DEVICE_TYPE(ELECTRON_AP1, electron_ap1_device, "electron_ap1", "P.R.E.S. Advanced Plus 1")
+DEFINE_DEVICE_TYPE(ELECTRON_AP6, electron_ap6_device, "electron_ap6", "P.R.E.S. Advanced Plus 6")
 
 
 //-------------------------------------------------
@@ -36,22 +38,33 @@ ROM_START( plus1 )
 	ROM_SYSTEM_BIOS(0, "plus1", "Expansion 1.00")
 	ROMX_LOAD("plus1.rom", 0x0000, 0x1000, CRC(ac30b0ed) SHA1(2de04ab7c81414d6c9c967f965c53fc276392463), ROM_BIOS(0))
 	ROM_RELOAD(            0x1000, 0x1000)
+ROM_END
 
-	ROM_SYSTEM_BIOS(1, "presap1", "PRES Expansion 1.1")
+ROM_START( ap1 )
-	ROMX_LOAD("presplus1.rom", 0x0000, 0x1000, CRC(8ef1e0e5) SHA1(080e1b788b3fe4fa272cd2cc792293eb7b874e82), ROM_BIOS(1))
+	// Bank 12 Expansion module operating system
+	ROM_REGION( 0x2000, "exp_rom", 0 )
+	ROM_DEFAULT_BIOS("ap2")
+	ROM_SYSTEM_BIOS(0, "ap1", "PRES Expansion 1.1")
+	ROMX_LOAD("presplus1.rom", 0x0000, 0x1000, CRC(8ef1e0e5) SHA1(080e1b788b3fe4fa272cd2cc792293eb7b874e82), ROM_BIOS(0))
 	ROM_RELOAD(                0x1000, 0x1000)
 
-	ROM_SYSTEM_BIOS(2, "presap2", "PRES AP2 Support 1.23")
+	ROM_SYSTEM_BIOS(1, "ap2", "PRES AP2 Support 1.23")
-	ROMX_LOAD("presap2_123.rom", 0x0000, 0x2000, CRC(f796689c) SHA1(bc40a79e6d2b4cb5e549d5d21f673c66a661850d), ROM_BIOS(2))
+	ROMX_LOAD("presap2_123.rom", 0x0000, 0x2000, CRC(f796689c) SHA1(bc40a79e6d2b4cb5e549d5d21f673c66a661850d), ROM_BIOS(1))
 
-	ROM_SYSTEM_BIOS(3, "sl200", "Slogger Expansion 2.00")
+	ROM_SYSTEM_BIOS(2, "ap6", "RH Plus 1 1.33")
-	ROMX_LOAD("elkexp200.rom", 0x0000, 0x2000, CRC(dee02843) SHA1(5c9b940b4ddb46e9a223160310683a32266300c8), ROM_BIOS(3))
+	ROMX_LOAD("ap6v133.rom", 0x0000, 0x2000, CRC(566c7bfe) SHA1(f1053109ea236dd3e4b91ec64859480e8c2ed549), ROM_BIOS(2))
+ROM_END
 
-	ROM_SYSTEM_BIOS(4, "sl201", "Slogger Expansion 2.01")
+ROM_START( ap6 )
-	ROMX_LOAD("elkexp201.rom", 0x0000, 0x2000, CRC(0e896892) SHA1(4e0794f1083fe529b01bd4fa100996a533ed8b10), ROM_BIOS(4))
+	// Bank 12 Expansion module operating system
+	ROM_REGION( 0x4000, "exp_rom", 0 )
+	ROM_DEFAULT_BIOS("ap6")
+	ROM_SYSTEM_BIOS(0, "ap2", "PRES AP2 Support 1.23")
+	ROMX_LOAD("presap2_123.rom", 0x0000, 0x2000, CRC(f796689c) SHA1(bc40a79e6d2b4cb5e549d5d21f673c66a661850d), ROM_BIOS(0))
+	ROM_RELOAD(                  0x2000, 0x2000)
 
-	ROM_SYSTEM_BIOS(5, "sl202", "Slogger Expansion 2.02")
+	ROM_SYSTEM_BIOS(1, "ap6", "RH Plus 1 1.33")
-	ROMX_LOAD("elkexp202.rom", 0x0000, 0x2000, CRC(32b440be) SHA1(dbc73e8d919c5615d0241d99db60e06324e16c86), ROM_BIOS(5))
+	ROMX_LOAD("ap6v133t.rom", 0x0000, 0x4000, CRC(364591eb) SHA1(316a25aeeda0266dae510eea52324b087875740f), ROM_BIOS(1))
 ROM_END
 
 //-------------------------------------------------
@@ -76,9 +89,23 @@ static INPUT_PORTS_START( plus1 )
 	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_BUTTON1) PORT_PLAYER(2)
 INPUT_PORTS_END
 
+static INPUT_PORTS_START( ap6 )
+	PORT_INCLUDE(plus1)
+
+	PORT_START("LINKS")
+	PORT_CONFNAME(0x01, 0x01, "J1 ROM 13")
+	PORT_CONFSETTING(0x00, "Disabled")
+	PORT_CONFSETTING(0x01, "Enabled")
+	PORT_CONFNAME(0x02, 0x02, "J2 ROM 4")
+	PORT_CONFSETTING(0x00, "Disabled")
+	PORT_CONFSETTING(0x02, "Enabled")
+	PORT_CONFNAME(0x04, 0x04, "J3 ROM 4,5,6,7")
+	PORT_CONFSETTING(0x00, "Disabled")
+	PORT_CONFSETTING(0x04, "Enabled")
+INPUT_PORTS_END
+
 //-------------------------------------------------
-//  machine_config_additions - device-specific
+//  input_ports - device-specific input ports
-//  machine configurations
 //-------------------------------------------------
 
 ioport_constructor electron_plus1_device::device_input_ports() const
@@ -86,6 +113,11 @@ ioport_constructor electron_plus1_device::device_input_ports() const
 	return INPUT_PORTS_NAME( plus1 );
 }
 
+ioport_constructor electron_ap6_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME( ap6 );
+}
+
 //-------------------------------------------------
 //  device_add_mconfig - add device configuration
 //-------------------------------------------------
@@ -94,13 +126,13 @@ void electron_plus1_device::device_add_mconfig(machine_config &config)
 {
 	/* printer */
 	CENTRONICS(config, m_centronics, centronics_devices, "printer");
-	m_centronics->busy_handler().set(FUNC(electron_plus1_device::busy_w));
+	m_centronics->busy_handler().set([this](int state) { m_centronics_busy = state; });
 	output_latch_device &latch(OUTPUT_LATCH(config, "cent_data_out"));
 	m_centronics->set_output_latch(latch);
 
 	/* adc */
 	ADC0844(config, m_adc);
-	m_adc->intr_callback().set(FUNC(electron_plus1_device::ready_w));
+	m_adc->intr_callback().set([this](int state) { m_adc_ready = !state; });
 	m_adc->ch1_callback().set_ioport("JOY1");
 	m_adc->ch2_callback().set_ioport("JOY2");
 	m_adc->ch3_callback().set_ioport("JOY3");
@@ -115,6 +147,25 @@ void electron_plus1_device::device_add_mconfig(machine_config &config)
 	m_cart_sk2->nmi_handler().set(DEVICE_SELF_OWNER, FUNC(electron_expansion_slot_device::nmi_w));
 }
 
+void electron_ap6_device::device_add_mconfig(machine_config &config)
+{
+	electron_plus1_device::device_add_mconfig(config);
+
+	/* rom sockets */
+	GENERIC_SOCKET(config, m_rom[0], generic_plain_slot, "electron_rom", "bin,rom");
+	m_rom[0]->set_device_load(FUNC(electron_ap6_device::rom1_load));
+	GENERIC_SOCKET(config, m_rom[1], generic_plain_slot, "electron_rom", "bin,rom");
+	m_rom[1]->set_device_load(FUNC(electron_ap6_device::rom2_load));
+	GENERIC_SOCKET(config, m_rom[2], generic_plain_slot, "electron_rom", "bin,rom");
+	m_rom[2]->set_device_load(FUNC(electron_ap6_device::rom3_load));
+	GENERIC_SOCKET(config, m_rom[3], generic_plain_slot, "electron_rom", "bin,rom");
+	m_rom[3]->set_device_load(FUNC(electron_ap6_device::rom4_load));
+	GENERIC_SOCKET(config, m_rom[4], generic_plain_slot, "electron_rom", "bin,rom");
+	m_rom[4]->set_device_load(FUNC(electron_ap6_device::rom5_load));
+	GENERIC_SOCKET(config, m_rom[5], generic_plain_slot, "electron_rom", "bin,rom");
+	m_rom[5]->set_device_load(FUNC(electron_ap6_device::rom6_load));
+}
+
 //-------------------------------------------------
 //  rom_region - device-specific ROM region
 //-------------------------------------------------
@@ -124,6 +175,16 @@ const tiny_rom_entry *electron_plus1_device::device_rom_region() const
 	return ROM_NAME( plus1 );
 }
 
+const tiny_rom_entry *electron_ap1_device::device_rom_region() const
+{
+	return ROM_NAME( ap1 );
+}
+
+const tiny_rom_entry *electron_ap6_device::device_rom_region() const
+{
+	return ROM_NAME( ap6 );
+}
+
 //**************************************************************************
 //  LIVE DEVICE
 //**************************************************************************
@@ -132,20 +193,37 @@ const tiny_rom_entry *electron_plus1_device::device_rom_region() const
 //  electron_plus1_device - constructor
 //-------------------------------------------------
 
-electron_plus1_device::electron_plus1_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+electron_plus1_device::electron_plus1_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock)
-	device_t(mconfig, ELECTRON_PLUS1, tag, owner, clock),
+	: device_t(mconfig, type, tag, owner, clock)
-	device_electron_expansion_interface(mconfig, *this),
+	, device_electron_expansion_interface(mconfig, *this)
-	m_exp_rom(*this, "exp_rom"),
+	, m_exp_rom(*this, "exp_rom")
-	m_cart_sk1(*this, "cart_sk1"),
+	, m_cart_sk1(*this, "cart_sk1")
-	m_cart_sk2(*this, "cart_sk2"),
+	, m_cart_sk2(*this, "cart_sk2")
-	m_centronics(*this, "centronics"),
+	, m_centronics(*this, "centronics")
-	m_cent_data_out(*this, "cent_data_out"),
+	, m_cent_data_out(*this, "cent_data_out")
-	m_adc(*this, "adc"),
+	, m_adc(*this, "adc")
-	m_joy(*this, "JOY%u", 1),
+	, m_joy(*this, "JOY%u", 1)
-	m_buttons(*this, "BUTTONS"),
+	, m_buttons(*this, "BUTTONS")
-	m_romsel(0),
+	, m_romsel(0)
-	m_centronics_busy(0),
+	, m_centronics_busy(0)
-	m_adc_ready(0)
+	, m_adc_ready(0)
+{
+}
+
+electron_plus1_device::electron_plus1_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+	: electron_plus1_device(mconfig, ELECTRON_PLUS1, tag, owner, clock)
+{
+}
+
+electron_ap1_device::electron_ap1_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+	: electron_plus1_device(mconfig, ELECTRON_AP1, tag, owner, clock)
+{
+}
+
+electron_ap6_device::electron_ap6_device(const machine_config& mconfig, const char* tag, device_t* owner, uint32_t clock)
+	: electron_plus1_device(mconfig, ELECTRON_AP6, tag, owner, clock)
+	, m_rom(*this, "rom%u", 1)
+	, m_links(*this, "LINKS")
 {
 }
 
@@ -156,6 +234,23 @@ electron_plus1_device::electron_plus1_device(const machine_config &mconfig, cons
 
 void electron_plus1_device::device_start()
 {
+	/* register for save states */
+	save_item(NAME(m_romsel));
+}
+
+void electron_ap6_device::device_start()
+{
+	electron_plus1_device::device_start();
+
+	m_ram = make_unique_clear<uint8_t[]>(0x18000);
+	memset(m_ram.get(), 0xff, 0x18000);
+
+	m_bank_locked[0] = false;
+	m_bank_locked[1] = false;
+
+	/* register for save states */
+	save_pointer(NAME(m_ram), 0x18000);
+	save_item(NAME(m_bank_locked));
 }
 
 
@@ -169,10 +264,7 @@ uint8_t electron_plus1_device::expbus_r(offs_t offset)
 
 	switch (offset >> 12)
 	{
-	case 0x8:
+	case 0x8: case 0x9: case 0xa: case 0xb:
-	case 0x9:
-	case 0xa:
-	case 0xb:
 		switch (m_romsel)
 		{
 		case 0:
@@ -206,7 +298,11 @@ uint8_t electron_plus1_device::expbus_r(offs_t offset)
 			}
 			else if (offset == 0xfc72)
 			{
-				data &= status_r();
+				// Status: b7: printer Busy
+				//         b6: ADC conversion end
+				//         b5: Fire Button 1
+				//         b4: Fire Button 2
+				data &= (m_centronics_busy << 7) | (m_adc_ready << 6) | m_buttons->read() | 0x0f;
 			}
 			break;
 
@@ -221,6 +317,63 @@ uint8_t electron_plus1_device::expbus_r(offs_t offset)
 }
 
 
+uint8_t electron_ap6_device::expbus_r(offs_t offset)
+{
+	uint8_t data = electron_plus1_device::expbus_r(offset);
+
+	switch (offset >> 12)
+	{
+	case 0x8: case 0x9: case 0xa: case 0xb:
+		switch (m_romsel)
+		{
+		case 4:
+			if (BIT(m_links->read(), 1) && BIT(m_links->read(), 2)) // ROM 4 enabled
+			{
+				if (m_rom[m_romsel - 4]->exists())
+					data = m_rom[m_romsel - 4]->read_rom(offset & 0x3fff);
+				else
+					data = m_ram[(m_romsel - 4) << 14 | (offset & 0x3fff)];
+			}
+			break;
+
+		case 5: case 6: case 7:
+			if (BIT(m_links->read(), 2)) // ROM 4,5,6,7 enabled
+			{
+				if (m_rom[m_romsel - 4]->exists())
+					data = m_rom[m_romsel - 4]->read_rom(offset & 0x3fff);
+				else
+					data = m_ram[(m_romsel - 4) << 14 | (offset & 0x3fff)];
+			}
+			break;
+
+		case 12:
+			data = m_exp_rom->base()[offset & 0x3fff];
+			break;
+
+		case 13:
+			if (BIT(m_links->read(), 0)) // ROM 13 enabled
+			{
+				if (m_rom[m_romsel - 9]->exists())
+					data &= m_rom[m_romsel - 9]->read_rom(offset & 0x3fff);
+				else
+					data &= m_ram[(m_romsel - 9) << 14 | (offset & 0x3fff)];
+			}
+			break;
+
+		case 14:
+			if (m_rom[m_romsel - 9]->exists())
+				data &= m_rom[m_romsel - 9]->read_rom(offset & 0x3fff);
+			else
+				data &= m_ram[(m_romsel - 9) << 14 | (offset & 0x3fff)];
+			break;
+		}
+		break;
+	}
+
+	return data;
+}
+
+
 //-------------------------------------------------
 //  expbus_w - expansion data write
 //-------------------------------------------------
@@ -229,10 +382,7 @@ void electron_plus1_device::expbus_w(offs_t offset, uint8_t data)
 {
 	switch (offset >> 12)
 	{
-	case 0x8:
+	case 0x8: case 0x9: case 0xa: case 0xb:
-	case 0x9:
-	case 0xa:
-	case 0xb:
 		switch (m_romsel)
 		{
 		case 0:
@@ -260,6 +410,8 @@ void electron_plus1_device::expbus_w(offs_t offset, uint8_t data)
 			else if (offset == 0xfc71)
 			{
 				m_cent_data_out->write(data);
+				m_centronics->write_strobe(0);
+				m_centronics->write_strobe(1);
 			}
 			break;
 
@@ -279,30 +431,100 @@ void electron_plus1_device::expbus_w(offs_t offset, uint8_t data)
 }
 
 
+void electron_ap6_device::expbus_w(offs_t offset, uint8_t data)
+{
+	electron_plus1_device::expbus_w(offset, data);
+
+	switch (offset >> 12)
+	{
+	case 0x8: case 0x9: case 0xa: case 0xb:
+		switch (m_romsel)
+		{
+		case 4:
+			if (BIT(m_links->read(), 1) && BIT(m_links->read(), 2)) // ROM 4 enabled
+			{
+				if (!m_rom[m_romsel - 4]->exists())
+					m_ram[(m_romsel - 4) << 14 | (offset & 0x3fff)] = data;
+			}
+			break;
+
+		case 7:
+			if (BIT(m_links->read(), 2)) // ROM 4,5,6,7 enabled
+			{
+				if (!m_rom[m_romsel - 4]->exists())
+					m_ram[(m_romsel - 4) << 14 | (offset & 0x3fff)] = data;
+			}
+			break;
+
+		case 5: case 6:
+			if (BIT(m_links->read(), 2)) // ROM 4,5,6,7 enabled
+			{
+				if (!m_rom[m_romsel - 4]->exists() && !m_bank_locked[0])
+					m_ram[(m_romsel - 4) << 14 | (offset & 0x3fff)] = data;
+			}
+			break;
+
+		case 13:
+			if (BIT(m_links->read(), 0)) // ROM 13 enabled
+			{
+				if (!m_rom[m_romsel - 9]->exists() && !m_bank_locked[1])
+					m_ram[(m_romsel - 9) << 14 | (offset & 0x3fff)] = data;
+			}
+			break;
+
+		case 14:
+			if (!m_rom[m_romsel - 9]->exists())
+				m_ram[(m_romsel - 9) << 14 | (offset & 0x3fff)] = data;
+			break;
+		}
+		break;
+
+	case 0xf:
+		switch (offset >> 8)
+		{
+		case 0xfc:
+			switch (offset & 0xff)
+			{
+			case 0xdc:
+				m_bank_locked[0] = false;
+				break;
+			case 0xdd:
+				m_bank_locked[0] = true;
+				break;
+			case 0xde:
+				m_bank_locked[1] = false;
+				break;
+			case 0xdf:
+				m_bank_locked[1] = true;
+				break;
+			}
+			break;
+		}
+	}
+}
+
+
 //**************************************************************************
 //  IMPLEMENTATION
 //**************************************************************************
 
-u8 electron_plus1_device::status_r()
+image_init_result electron_ap6_device::load_rom(device_image_interface &image, generic_slot_device *slot)
 {
-	u8 data = 0x0f;
+	uint32_t size = slot->common_get_size("rom");
-	// Status: b7: printer Busy
-	//         b6: ADC conversion end
-	//         b5: Fire Button 1
-	//         b4: Fire Button 2
-	data |= (m_centronics_busy << 7);
-	data |= (m_adc_ready << 6);
-	data |= m_buttons->read();
 
-	return data;
+	// socket accepts 8K and 16K ROM only
-}
+	if (size != 0x2000 && size != 0x4000)
+	{
+		image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size: Only 8K/16K is supported");
+		return image_init_result::FAIL;
+	}
 
-WRITE_LINE_MEMBER(electron_plus1_device::busy_w)
+	slot->rom_alloc(0x4000, GENERIC_ROM8_WIDTH, ENDIANNESS_LITTLE);
-{
+	slot->common_load_rom(slot->get_rom_base(), size, "rom");
-	m_centronics_busy = !state;
-}
 
-WRITE_LINE_MEMBER(electron_plus1_device::ready_w)
+	// mirror 8K ROMs
-{
+	uint8_t *crt = slot->get_rom_base();
-	m_adc_ready = !state;
+	if (size <= 0x2000) memcpy(crt + 0x2000, crt, 0x2000);
+
+	return image_init_result::PASS;
 }

src/devices/bus/electron/plus1.h

@@ -11,10 +11,11 @@
 #define MAME_BUS_ELECTRON_PLUS1_H
 
 #include "exp.h"
-#include "softlist.h"
 #include "machine/adc0844.h"
 #include "bus/centronics/ctronics.h"
 #include "bus/electron/cart/slot.h"
+#include "bus/generic/slot.h"
+#include "bus/generic/carts.h"
 
 //**************************************************************************
 //  TYPE DEFINITIONS
@@ -29,6 +30,8 @@ public:
 	electron_plus1_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
 
 protected:
+	electron_plus1_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
+
 	// device-level overrides
 	virtual void device_start() override;
 
@@ -40,11 +43,6 @@ protected:
 	virtual uint8_t expbus_r(offs_t offset) override;
 	virtual void expbus_w(offs_t offset, uint8_t data) override;
 
-private:
-	u8 status_r();
-	DECLARE_WRITE_LINE_MEMBER(busy_w);
-	DECLARE_WRITE_LINE_MEMBER(ready_w);
-
 	required_memory_region m_exp_rom;
 	required_device<electron_cartslot_device> m_cart_sk1;
 	required_device<electron_cartslot_device> m_cart_sk2;
@@ -60,8 +58,56 @@ private:
 };
 
 
+class electron_ap1_device : public electron_plus1_device
+{
+public:
+	electron_ap1_device(const machine_config& mconfig, const char* tag, device_t* owner, uint32_t clock);
+
+protected:
+	// optional information overrides
+	virtual const tiny_rom_entry* device_rom_region() const override;
+};
+
+
+class electron_ap6_device : public electron_plus1_device
+{
+public:
+	electron_ap6_device(const machine_config& mconfig, const char* tag, device_t* owner, uint32_t clock);
+
+protected:
+	// device-level overrides
+	virtual void device_start() override;
+
+	// optional information overrides
+	virtual void device_add_mconfig(machine_config& config) override;
+	virtual const tiny_rom_entry* device_rom_region() const override;
+	virtual ioport_constructor device_input_ports() const override;
+
+	virtual uint8_t expbus_r(offs_t offset) override;
+	virtual void expbus_w(offs_t offset, uint8_t data) override;
+
+private:
+	image_init_result load_rom(device_image_interface &image, generic_slot_device *slot);
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER(rom1_load) { return load_rom(image, m_rom[0]); }
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER(rom2_load) { return load_rom(image, m_rom[1]); }
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER(rom3_load) { return load_rom(image, m_rom[2]); }
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER(rom4_load) { return load_rom(image, m_rom[3]); }
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER(rom5_load) { return load_rom(image, m_rom[4]); }
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER(rom6_load) { return load_rom(image, m_rom[5]); }
+
+	required_device_array<generic_slot_device, 6> m_rom;
+	required_ioport m_links;
+
+	std::unique_ptr<uint8_t[]> m_ram;
+	bool m_bank_locked[2];
+};
+
+
+
 // device type definition
 DECLARE_DEVICE_TYPE(ELECTRON_PLUS1, electron_plus1_device)
+DECLARE_DEVICE_TYPE(ELECTRON_AP1, electron_ap1_device)
+DECLARE_DEVICE_TYPE(ELECTRON_AP6, electron_ap6_device)
 
 
 #endif /* MAME_BUS_ELECTRON_PLUS1_H */