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-rw-r--r--src/devices/bus/a2bus/a2midi.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/src/devices/bus/a2bus/a2midi.c b/src/devices/bus/a2bus/a2midi.c
new file mode 100644
index 00000000000..92dbff70520
--- /dev/null
+++ b/src/devices/bus/a2bus/a2midi.c
@@ -0,0 +1,172 @@
+// license:BSD-3-Clause
+// copyright-holders:R. Belmont
+/*********************************************************************
+
+ a2midi.c
+
+ Apple II 6850 MIDI card, as made by Passport, Yamaha, and others.
+
+*********************************************************************/
+
+#include "a2midi.h"
+#include "machine/clock.h"
+#include "bus/midi/midi.h"
+
+
+/***************************************************************************
+ PARAMETERS
+***************************************************************************/
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+const device_type A2BUS_MIDI = &device_creator<a2bus_midi_device>;
+
+#define MIDI_PTM_TAG "midi_ptm"
+#define MIDI_ACIA_TAG "midi_acia"
+
+MACHINE_CONFIG_FRAGMENT( midi )
+ MCFG_DEVICE_ADD(MIDI_PTM_TAG, PTM6840, 0)
+ MCFG_PTM6840_INTERNAL_CLOCK(1021800.0f)
+ MCFG_PTM6840_EXTERNAL_CLOCKS(1021800.0f, 1021800.0f, 1021800.0f)
+ MCFG_PTM6840_IRQ_CB(WRITELINE(a2bus_midi_device, ptm_irq_w))
+
+ MCFG_DEVICE_ADD(MIDI_ACIA_TAG, ACIA6850, 0)
+ MCFG_ACIA6850_TXD_HANDLER(DEVWRITELINE("mdout", midi_port_device, write_txd))
+ MCFG_ACIA6850_IRQ_HANDLER(WRITELINE(a2bus_midi_device, acia_irq_w))
+
+ MCFG_MIDI_PORT_ADD("mdin", midiin_slot, "midiin")
+ MCFG_MIDI_RX_HANDLER(DEVWRITELINE(MIDI_ACIA_TAG, acia6850_device, write_rxd))
+
+ MCFG_MIDI_PORT_ADD("mdout", midiout_slot, "midiout")
+
+ MCFG_DEVICE_ADD("acia_clock", CLOCK, 31250*16)
+ MCFG_CLOCK_SIGNAL_HANDLER(WRITELINE(a2bus_midi_device, write_acia_clock))
+MACHINE_CONFIG_END
+
+//-------------------------------------------------
+// machine_config_additions - device-specific
+// machine configurations
+//-------------------------------------------------
+
+machine_config_constructor a2bus_midi_device::device_mconfig_additions() const
+{
+ return MACHINE_CONFIG_NAME( midi );
+}
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+a2bus_midi_device::a2bus_midi_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, A2BUS_MIDI, "6850 MIDI card", tag, owner, clock, "a2midi", __FILE__),
+ device_a2bus_card_interface(mconfig, *this),
+ m_ptm(*this, MIDI_PTM_TAG),
+ m_acia(*this, MIDI_ACIA_TAG),
+ m_ptm_irq(false)
+{
+}
+
+a2bus_midi_device::a2bus_midi_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source) :
+ device_t(mconfig, type, name, tag, owner, clock, shortname, source),
+ device_a2bus_card_interface(mconfig, *this),
+ m_ptm(*this, MIDI_PTM_TAG),
+ m_acia(*this, MIDI_ACIA_TAG),
+ m_ptm_irq(false)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void a2bus_midi_device::device_start()
+{
+ // set_a2bus_device makes m_slot valid
+ set_a2bus_device();
+}
+
+void a2bus_midi_device::device_reset()
+{
+ m_acia_irq = m_ptm_irq = false;
+}
+
+/*-------------------------------------------------
+ read_c0nx - called for reads from this card's c0nx space
+-------------------------------------------------*/
+
+UINT8 a2bus_midi_device::read_c0nx(address_space &space, UINT8 offset)
+{
+ // PTM at C0n0-C0n7, ACIA at C0n8-C0n9, drum sync (?) at C0nA-C0nB
+
+ if (offset < 8)
+ {
+ return m_ptm->read(space, offset & 7);
+ }
+ else if (offset == 8)
+ {
+ return m_acia->status_r(space, 0);
+ }
+ else if (offset == 9)
+ {
+ UINT8 ret = m_acia->data_r(space, 0);
+ return ret;
+ }
+
+ return 0;
+}
+
+/*-------------------------------------------------
+ write_c0nx - called for writes to this card's c0nx space
+-------------------------------------------------*/
+
+void a2bus_midi_device::write_c0nx(address_space &space, UINT8 offset, UINT8 data)
+{
+ if (offset < 8)
+ {
+ m_ptm->write(space, offset & 7, data);
+ }
+ else if (offset == 8)
+ {
+ m_acia->control_w(space, 0, data);
+ }
+ else if (offset == 9)
+ {
+ m_acia->data_w(space, 0, data);
+ }
+}
+
+WRITE_LINE_MEMBER( a2bus_midi_device::acia_irq_w )
+{
+ m_acia_irq = state ? true : false;
+
+ if (m_acia_irq || m_ptm_irq)
+ {
+ raise_slot_irq();
+ }
+ else
+ {
+ lower_slot_irq();
+ }
+}
+
+WRITE_LINE_MEMBER( a2bus_midi_device::ptm_irq_w )
+{
+ m_acia_irq = state ? true : false;
+
+ if (m_acia_irq || m_ptm_irq)
+ {
+ raise_slot_irq();
+ }
+ else
+ {
+ lower_slot_irq();
+ }
+}
+
+WRITE_LINE_MEMBER( a2bus_midi_device::write_acia_clock )
+{
+ m_acia->write_txc(state);
+ m_acia->write_rxc(state);
+}