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-rw-r--r--src/devices/bus/coco/coco_psg.cpp270
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diff --git a/src/devices/bus/coco/coco_psg.cpp b/src/devices/bus/coco/coco_psg.cpp
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+++ b/src/devices/bus/coco/coco_psg.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Roberto Fernandez,Nigel Barnes
+// thanks-to:Ed Snider
+/***************************************************************************
+
+ coco_psg.cpp
+
+ Code for emulating the CoCo PSG. A banked switched ROM and RAM cartridge
+ with a YM2149 programmable sound generator and two digital Atari-compatible
+ joystick ports.
+
+ Cartridge by Ed Snider.
+
+ CoCo PSG site:
+ https://thezippsterzone.com/2018/05/08/coco-psg/
+
+ CoCo PSG manual:
+ https://thezippsterzone.com/wp-content/uploads/2018/05/coco-psg-users-manual.pdf
+
+***************************************************************************/
+
+#include "emu.h"
+#include "coco_psg.h"
+#include "speaker.h"
+
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE_PRIVATE(COCO_PSG, device_cococart_interface, coco_psg_device, "coco_psg", "CoCo PSG")
+
+
+//-------------------------------------------------
+// ROM( cocopsg )
+//-------------------------------------------------
+
+ROM_START(cocopsg)
+ ROM_REGION(0x80000, "flash", 0)
+ ROM_LOAD("psg_firmware_v1.bin", 0x0000, 0x80000, CRC(5de614f8) SHA1(9c7c8a5cc419ca1aca4d1c5e9f1195997c2bc95c))
+ROM_END
+
+//-------------------------------------------------
+// rom_region - device-specific ROM region
+//-------------------------------------------------
+
+const tiny_rom_entry *coco_psg_device::device_rom_region() const
+{
+ return ROM_NAME(cocopsg);
+}
+
+//-------------------------------------------------
+// INPUT_PORTS( cocopsg )
+//-------------------------------------------------
+
+static INPUT_PORTS_START(cocopsg)
+ PORT_START("GAMEPORT_A")
+ PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_JOYSTICK_UP) PORT_8WAY PORT_PLAYER(1)
+ PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN) PORT_8WAY PORT_PLAYER(1)
+ PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT) PORT_8WAY PORT_PLAYER(1)
+ PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT) PORT_8WAY PORT_PLAYER(1)
+ PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_BUTTON1) PORT_PLAYER(1)
+ PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_BUTTON2) PORT_PLAYER(1)
+ PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_UNUSED)
+ PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_UNUSED)
+
+ PORT_START("GAMEPORT_B")
+ PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_JOYSTICK_UP) PORT_8WAY PORT_PLAYER(2)
+ PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN) PORT_8WAY PORT_PLAYER(2)
+ PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT) PORT_8WAY PORT_PLAYER(2)
+ PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT) PORT_8WAY PORT_PLAYER(2)
+ PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_BUTTON1) PORT_PLAYER(2)
+ PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_BUTTON2) PORT_PLAYER(2)
+ PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_UNUSED)
+ PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_UNUSED)
+INPUT_PORTS_END
+
+//-------------------------------------------------
+// input_ports - device-specific input ports
+//-------------------------------------------------
+
+ioport_constructor coco_psg_device::device_input_ports() const
+{
+ return INPUT_PORTS_NAME(cocopsg);
+}
+
+//-------------------------------------------------
+// device_add_mconfig - add device configuration
+//-------------------------------------------------
+
+void coco_psg_device::device_add_mconfig(machine_config &config)
+{
+ SPEAKER(config, "speaker").front_center();
+ YM2149(config, m_psg, 1_MHz_XTAL);
+ m_psg->port_a_read_callback().set_ioport("GAMEPORT_A");
+ m_psg->port_b_read_callback().set_ioport("GAMEPORT_B");
+ m_psg->add_route(ALL_OUTPUTS, "speaker", 1.0);
+
+ SST_39SF040(config, "flash");
+}
+
+
+//-------------------------------------------------
+// coco_psg_device - constructor
+//-------------------------------------------------
+
+coco_psg_device::coco_psg_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+ : device_t(mconfig, COCO_PSG, tag, owner, clock)
+ , device_cococart_interface(mconfig, *this)
+ , m_psg(*this, "psg")
+ , m_flash(*this, "flash")
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void coco_psg_device::device_start()
+{
+ m_sram = std::make_unique<u8[]>(0x80000);
+
+ /* registers are set to a default of zero */
+ m_bank[0] = 0x00;
+ m_bank[1] = 0x00;
+ m_control = 0x00;
+
+ set_line_value(line::CART, line_value::Q);
+
+ /* register for save states */
+ save_item(NAME(m_bank));
+ save_item(NAME(m_control));
+ save_pointer(NAME(m_sram), 0x80000);
+}
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void coco_psg_device::device_reset()
+{
+ install_write_handler(0xb555, 0xb555, write8sm_delegate(*this, FUNC(coco_psg_device::flash5555_w)));
+ install_write_handler(0xbaaa, 0xbaaa, write8sm_delegate(*this, FUNC(coco_psg_device::flash2aaa_w)));
+}
+
+void coco_psg_device::flash2aaa_w(offs_t offset, u8 data)
+{
+ if (BIT(m_control, 5) && BIT(m_control, 3))
+ {
+ m_flash->write(0x2aaa, data);
+ }
+}
+
+void coco_psg_device::flash5555_w(offs_t offset, u8 data)
+{
+ if (BIT(m_control, 5) && BIT(m_control, 3))
+ {
+ m_flash->write(0x5555, data);
+ }
+}
+
+//-------------------------------------------------
+// scs_read
+//-------------------------------------------------
+
+u8 coco_psg_device::scs_read(offs_t offset)
+{
+ u8 data = 0x00;
+
+ switch (offset)
+ {
+ case 0x1a:
+ case 0x1b:
+ /* memory bank register */
+ data = m_bank[BIT(offset, 0)];
+ break;
+
+ case 0x1f:
+ /* ym data port */
+ data = m_psg->data_r();
+ break;
+ }
+
+ return data;
+}
+
+//-------------------------------------------------
+// scs_write
+//-------------------------------------------------
+
+void coco_psg_device::scs_write(offs_t offset, u8 data)
+{
+ switch (offset)
+ {
+ case 0x1a:
+ case 0x1b:
+ /* memory bank register */
+ m_bank[BIT(offset, 0)] = data;
+ break;
+
+ case 0x1d:
+ /* control register
+ BIT FUNCTION
+ 0 YM2149 MASTER CLOCK; 0=2MHz, 1=1MHz
+ 1 Gameport A SEL signal (pin 7 of controller port A)
+ 2 Gameport B SEL signal (pin 7 of controller port B)
+ 3 Write Enable (for FLASH/SRAM); 0=disabled, 1=enabled
+ 4 Autostart enable; 0=enabled, 1=disabled
+ 5 FLASH programming enable; 0=disabled, 1=enabled
+ 6 not used
+ 7 not used
+ */
+ m_control = data;
+
+ /* bit 0 - YM2149 MASTER CLOCK; 0=2MHz, 1=1MHz */
+ if (BIT(data, 0))
+ m_psg->set_pin26_low_w();
+ else
+ m_psg->set_pin26_high_w();
+
+ /* bit 4 - Autostart enable; 0=enabled, 1=disabled */
+ set_line_value(line::CART, BIT(data, 4) ? line_value::CLEAR : line_value::Q);
+ break;
+
+ case 0x1e:
+ /* ym register select port*/
+ m_psg->address_w(data & 0x0f);
+ break;
+ case 0x1f:
+ /* ym data port */
+ m_psg->data_w(data);
+ break;
+ }
+}
+
+
+//-------------------------------------------------
+// cts_read
+//-------------------------------------------------
+
+u8 coco_psg_device::cts_read(offs_t offset)
+{
+ u8 data = 0x00;
+
+ if (m_bank[BIT(offset, 13)] & 0x80)
+ {
+ data = m_sram[(offset & 0x1fff) | (m_bank[BIT(offset, 13)] & 0x3f) << 13];
+ }
+ else
+ {
+ data = m_flash->read_raw((offset & 0x1fff) | (m_bank[BIT(offset, 13)] & 0x3f) << 13);
+ }
+
+ return data;
+}
+
+//-------------------------------------------------
+// cts_write
+//-------------------------------------------------
+
+void coco_psg_device::cts_write(offs_t offset, u8 data)
+{
+ if (BIT(m_control, 3))
+ {
+ if (m_bank[BIT(offset, 13)] & 0x80)
+ {
+ m_sram[(offset & 0x1fff) | (m_bank[BIT(offset, 13)] & 0x3f) << 13] = data;
+ }
+ }
+}