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Diffstat (limited to 'src/devices/bus/pc8801/pc8801_23.cpp')
-rw-r--r--src/devices/bus/pc8801/pc8801_23.cpp89
1 files changed, 89 insertions, 0 deletions
diff --git a/src/devices/bus/pc8801/pc8801_23.cpp b/src/devices/bus/pc8801/pc8801_23.cpp
new file mode 100644
index 00000000000..507f4e49c7b
--- /dev/null
+++ b/src/devices/bus/pc8801/pc8801_23.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Angelo Salese
+/**************************************************************************************************
+
+ NEC PC-8801-23 / -24 / -25 "Sound Board II"
+
+ TODO:
+ - Irq hangs if there's a PC-8801 OPN/OPNA declared in driver.
+ Master OPNA keeps sending acks in the correlated INT4 handler that hampers irq
+ signals from here;
+ - Confirm there's no DB9 joyport on any variants of this;
+
+**************************************************************************************************/
+
+#include "emu.h"
+#include "pc8801_23.h"
+
+DEFINE_DEVICE_TYPE(PC8801_23, pc8801_23_device, "pc8801_23", "NEC PC-8801-23 \"Sound Board II\"")
+
+pc8801_23_device::pc8801_23_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : pc8801_exp_device(mconfig, PC8801_23, tag, owner, clock)
+ , m_opna(*this, "opna")
+{
+}
+
+void pc8801_23_device::io_map(address_map &map)
+{
+ map(0xa8, 0xa9).rw(m_opna, FUNC(ym2608_device::read), FUNC(ym2608_device::write));
+ map(0xaa, 0xaa).rw(FUNC(pc8801_23_device::irq_status_r), FUNC(pc8801_23_device::irq_mask_w));
+ map(0xac, 0xad).lrw8(
+ NAME([this] (offs_t offset) { return m_opna->read(offset | 2); }),
+ NAME([this] (offs_t offset, u8 data) { m_opna->write(offset | 2, data); })
+ );
+}
+
+void pc8801_23_device::opna_map(address_map &map)
+{
+ // TODO: confirm it really is ROMless
+ // TODO: confirm size
+ map(0x000000, 0x1fffff).ram();
+}
+
+void pc8801_23_device::device_add_mconfig(machine_config &config)
+{
+ constexpr XTAL sound_clock = XTAL(31'948'800) / 4;
+
+ YM2608(config, m_opna, sound_clock);
+ m_opna->set_addrmap(0, &pc8801_23_device::opna_map);
+ m_opna->irq_handler().set(FUNC(pc8801_23_device::int4_w));
+// m_opna->port_a_read_callback().set(FUNC(pc8801_23_device::opn_porta_r));
+// m_opna->port_b_read_callback().set_ioport("OPN_PB");
+ // TODO: per-channel mixing is unconfirmed
+ m_opna->add_route(0, "^^lspeaker", 0.25);
+ m_opna->add_route(0, "^^rspeaker", 0.25);
+ m_opna->add_route(1, "^^lspeaker", 0.75);
+ m_opna->add_route(2, "^^rspeaker", 0.75);
+}
+
+void pc8801_23_device::device_start()
+{
+ save_item(NAME(m_irq_mask));
+ save_item(NAME(m_irq_pending));
+}
+
+void pc8801_23_device::device_reset()
+{
+ m_irq_mask = true;
+ m_irq_pending = false;
+}
+
+u8 pc8801_23_device::irq_status_r()
+{
+ return 0x7f | (m_irq_mask << 7);
+}
+
+void pc8801_23_device::irq_mask_w(u8 data)
+{
+ m_irq_mask = bool(BIT(data, 7));
+
+ if (!m_irq_mask && m_irq_pending)
+ int4_w(m_irq_pending);
+}
+
+void pc8801_23_device::int4_w(int state)
+{
+ bool irq_state = (!m_irq_mask) & state;
+ pc8801_exp_device::int4_w(irq_state);
+ m_irq_pending = state;
+}