diff options
Diffstat (limited to 'src/mame/machine/m20_8086.c')
-rw-r--r-- | src/mame/machine/m20_8086.c | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/src/mame/machine/m20_8086.c b/src/mame/machine/m20_8086.c new file mode 100644 index 00000000000..5c817b17edf --- /dev/null +++ b/src/mame/machine/m20_8086.c @@ -0,0 +1,119 @@ +// license:BSD-3-Clause +// copyright-holders:Carl +#include "m20_8086.h" +#include "machine/ram.h" + +const device_type M20_8086 = &device_creator<m20_8086_device>; + +m20_8086_device::m20_8086_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : + device_t(mconfig, M20_8086, "Olivetti M20 8086 Adapter", tag, owner, clock, "m20_8086", __FILE__), + m_8086(*this, "8086"), + m_maincpu(*this, ":maincpu"), + m_pic(*this, ":i8259"), + m_8086_halt(true) +{ +} + +void m20_8086_device::device_start() +{ + UINT8* ram = machine().device<ram_device>("ram")->pointer(); + m_8086->space(AS_PROGRAM).install_readwrite_bank(0x00000, machine().device<ram_device>("ram")->size() - 0x4001, "mainram"); + membank("highram")->set_base(ram); + membank("mainram")->set_base(&ram[0x4000]); + membank("vram")->set_base(memshare(":p_videoram")->ptr()); + membank("vram2")->set_base(memshare(":p_videoram")->ptr()); +} + +void m20_8086_device::device_reset() +{ + m_8086_halt = true; + m_nvi = m_vi = 0; + m_8086->set_input_line(INPUT_LINE_HALT, ASSERT_LINE); +} + +ROM_START( m20_8086 ) + ROM_REGION(0x4000, "8086", 0) + ROM_LOAD("apb-1086-2.0.bin", 0x0000, 0x4000, CRC(8c05be93) SHA1(2bb424afd874cc6562e9642780eaac2391308053)) +ROM_END + + +const rom_entry *m20_8086_device::device_rom_region() const +{ + return ROM_NAME( m20_8086 ); +} + +static ADDRESS_MAP_START(i86_prog, AS_PROGRAM, 16, m20_8086_device) + AM_RANGE(0xe0000, 0xe3fff) AM_RAMBANK("vram2") + AM_RANGE(0xf0000, 0xf3fff) AM_RAMBANK("highram") + AM_RANGE(0xf4000, 0xf7fff) AM_RAMBANK("vram") + AM_RANGE(0xfc000, 0xfffff) AM_ROM AM_REGION("8086",0) +ADDRESS_MAP_END + +static ADDRESS_MAP_START(i86_io, AS_IO, 16, m20_8086_device) + AM_RANGE(0x4000, 0x4fff) AM_READWRITE(z8000_io_r, z8000_io_w) + AM_RANGE(0x7ffa, 0x7ffd) AM_WRITE(handshake_w) +ADDRESS_MAP_END + +static MACHINE_CONFIG_FRAGMENT( m20_8086 ) + MCFG_CPU_ADD("8086", I8086, XTAL_24MHz/3) + MCFG_CPU_PROGRAM_MAP(i86_prog) + MCFG_CPU_IO_MAP(i86_io) + MCFG_CPU_IRQ_ACKNOWLEDGE_DRIVER(m20_8086_device, int_cb) +MACHINE_CONFIG_END + +machine_config_constructor m20_8086_device::device_mconfig_additions() const +{ + return MACHINE_CONFIG_NAME( m20_8086 ); +} + +READ16_MEMBER(m20_8086_device::z8000_io_r) +{ + return m_maincpu->space(AS_IO).read_word(offset << 1, mem_mask); +} + +WRITE16_MEMBER(m20_8086_device::z8000_io_w) +{ + m_maincpu->space(AS_IO).write_word(offset << 1, data, mem_mask); +} + +IRQ_CALLBACK_MEMBER(m20_8086_device::int_cb) +{ + if(m_nvi) + { + m_nvi = false; + m_8086->set_input_line(INPUT_LINE_IRQ0, m_vi ? ASSERT_LINE : CLEAR_LINE); + return 0xff; + } + else + return m_pic->acknowledge() << 1; +} + +WRITE_LINE_MEMBER(m20_8086_device::nvi_w) +{ + m_nvi = state; + m_8086->set_input_line(INPUT_LINE_IRQ0, (state || m_vi) ? ASSERT_LINE : CLEAR_LINE); +} + +WRITE_LINE_MEMBER(m20_8086_device::vi_w) +{ + m_vi = state; + m_8086->set_input_line(INPUT_LINE_IRQ0, (state || m_nvi) ? ASSERT_LINE : CLEAR_LINE); +} + +WRITE16_MEMBER(m20_8086_device::handshake_w) +{ + if(!offset) + { + m_8086->set_input_line(INPUT_LINE_HALT, ASSERT_LINE); + m_maincpu->set_input_line(INPUT_LINE_HALT, CLEAR_LINE); + m_maincpu->set_input_line(INPUT_LINE_NMI, PULSE_LINE); + m_8086_halt = true; + } + else + { + m_8086->set_input_line(INPUT_LINE_HALT, CLEAR_LINE); + m_8086->set_input_line(INPUT_LINE_RESET, PULSE_LINE); + m_maincpu->set_input_line(INPUT_LINE_HALT, ASSERT_LINE); + m_8086_halt = false; + } +} |