diff options
Diffstat (limited to 'src/mame/homebrew/d6809.cpp')
-rw-r--r-- | src/mame/homebrew/d6809.cpp | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/src/mame/homebrew/d6809.cpp b/src/mame/homebrew/d6809.cpp new file mode 100644 index 00000000000..b77eb7a2463 --- /dev/null +++ b/src/mame/homebrew/d6809.cpp @@ -0,0 +1,231 @@ +// license:BSD-3-Clause +// copyright-holders:Robbbert +/******************************************************************************* + +Dunfield 6809 Portable + +2009-05-12 Skeleton driver. +2011-09-21 connected to terminal, notes added [Robbbert] + +Chips used (planned?): +- 6809E CPU +- 6845 CRTC +- 6840 CTC +- 6551 ACIA Console +- 6551 ACIA Aux +- 6850 ACIA Unknown purpose +- uPD765 FDC +- 2764 8K ROM for CPU +- 2732 4K ROM for Chargen (not dumped) +- 6x 6264 RAM +- 3x 5516 RAM +- XTALs: 14.745MHz, 16MHz + +So much for the official documentation. + +In practice, it reads/writes to a terminal, and doesn't use most of the other +devices. + +'maincpu' (F9DD): unmapped program memory write to 00F0 = 05 & FF +'maincpu' (F9E3): unmapped program memory read from 0001 & FF <----- these 2 are CLR 0001 +'maincpu' (F9E3): unmapped program memory write to 0001 = 00 & FF +'maincpu' (F9E6): unmapped program memory read from 0005 & FF <----- these 2 are CLR 0005 +'maincpu' (F9E6): unmapped program memory write to 0005 = 00 & FF +'maincpu' (F9E9): unmapped program memory write to 0002 = 0B & FF <-- these 2 are STD 0002 +'maincpu' (F9E9): unmapped program memory write to 0003 = 1E & FF +'maincpu' (F9EC): unmapped program memory write to 0006 = 0B & FF <-- these 2 are STD 0006 +'maincpu' (F9EC): unmapped program memory write to 0007 = 1E & FF +'maincpu' (FA4D): unmapped program memory write to 00F2 = 00 & FF <-- the remainder seems to be disk related +'maincpu' (FA52): unmapped program memory write to 00F3 = 00 & FF +'maincpu' (FA57): unmapped program memory write to 00F4 = 00 & FF +'maincpu' (FA5C): unmapped program memory write to 00F5 = 00 & FF +'maincpu' (FA61): unmapped program memory write to 00F6 = 02 & FF +'maincpu' (FA66): unmapped program memory write to 00F7 = 09 & FF +'maincpu' (FA6B): unmapped program memory write to 00F0 = 01 & FF +'maincpu' (FA6E): unmapped program memory read from 00F0 & FF +'maincpu' (FA4D): unmapped program memory write to 00F2 = 00 & FF +'maincpu' (FA52): unmapped program memory write to 00F3 = 00 & FF +'maincpu' (FA57): unmapped program memory write to 00F4 = 00 & FF +'maincpu' (FA5C): unmapped program memory write to 00F5 = 00 & FF +'maincpu' (FA61): unmapped program memory write to 00F6 = 02 & FF +'maincpu' (FA66): unmapped program memory write to 00F7 = 09 & FF +'maincpu' (FA6B): unmapped program memory write to 00F0 = 01 & FF +'maincpu' (FA6E): unmapped program memory read from 00F0 & FF +'maincpu' (FA4D): unmapped program memory write to 00F2 = 00 & FF +'maincpu' (FA52): unmapped program memory write to 00F3 = 00 & FF +'maincpu' (FA57): unmapped program memory write to 00F4 = 00 & FF +'maincpu' (FA5C): unmapped program memory write to 00F5 = 00 & FF +'maincpu' (FA61): unmapped program memory write to 00F6 = 02 & FF +'maincpu' (FA66): unmapped program memory write to 00F7 = 09 & FF +'maincpu' (FA6B): unmapped program memory write to 00F0 = 01 & FF +'maincpu' (FA6E): unmapped program memory read from 00F0 & FF +'maincpu' (FA41): unmapped program memory write to 00F2 = 00 & FF +'maincpu' (FA46): unmapped program memory write to 00F0 = 04 & FF +'maincpu' (FA82): unmapped program memory read from 00F0 & FF +'maincpu' (FA4D): unmapped program memory write to 00F2 = 00 & FF +'maincpu' (FA52): unmapped program memory write to 00F3 = 00 & FF +'maincpu' (FA57): unmapped program memory write to 00F4 = 00 & FF +'maincpu' (FA5C): unmapped program memory write to 00F5 = 00 & FF +'maincpu' (FA61): unmapped program memory write to 00F6 = 02 & FF +'maincpu' (FA66): unmapped program memory write to 00F7 = 09 & FF +'maincpu' (FA6B): unmapped program memory write to 00F0 = 01 & FF +'maincpu' (FA6E): unmapped program memory read from 00F0 & FF +'maincpu' (FA4D): unmapped program memory write to 00F2 = 00 & FF +'maincpu' (FA52): unmapped program memory write to 00F3 = 00 & FF +'maincpu' (FA57): unmapped program memory write to 00F4 = 00 & FF +'maincpu' (FA5C): unmapped program memory write to 00F5 = 00 & FF +'maincpu' (FA61): unmapped program memory write to 00F6 = 02 & FF +'maincpu' (FA66): unmapped program memory write to 00F7 = 09 & FF +'maincpu' (FA6B): unmapped program memory write to 00F0 = 01 & FF +'maincpu' (FA6E): unmapped program memory read from 00F0 & FF <-- now it gives up & prints an error + + +Layout of devices differences: + Schematic Actual +6551 1 0000 0000 +6551 2 0100 0004 +Disk status 0400 00F0 +Disk commands 0401 00F0-00F7 +Parallel terminal not there 00FF +CE on UPD765 0400 0200 +TC on UPD765 0500 0300 + +Also, pins 16,17,18 on the UPD765 are incorrect in the schematic. + + +ToDo: +- Need better documentation +- Need a boot disk image + +**********************************************************************************/ + +#include "emu.h" +#include "cpu/m6809/m6809.h" +#include "imagedev/floppy.h" +#include "machine/mos6551.h" +#include "machine/upd765.h" +#include "machine/terminal.h" + + +namespace { + +class d6809_state : public driver_device +{ +public: + d6809_state(const machine_config &mconfig, device_type type, const char *tag) + : driver_device(mconfig, type, tag) + , m_maincpu(*this, "maincpu") + , m_terminal(*this, "terminal") + , m_fdc(*this, "fdc") + , m_floppy0(*this, "fdc:0") + { } + + void d6809(machine_config &config); + +private: + u8 term_r(); + void term_w(u8 data); + void kbd_put(u8 data); + + void mem_map(address_map &map) ATTR_COLD; + + u8 m_term_data = 0U; + void machine_start() override ATTR_COLD; + void machine_reset() override ATTR_COLD; + required_device<cpu_device> m_maincpu; + required_device<generic_terminal_device> m_terminal; + required_device<upd765a_device> m_fdc; + required_device<floppy_connector> m_floppy0; +}; + +u8 d6809_state::term_r() +{ + u8 ret = m_term_data; + m_term_data = 0; + return ret; +} + +void d6809_state::term_w(u8 data) +{ + if ((data > 0) && (data < 0x80)) + m_terminal->write(data); +} + +void d6809_state::mem_map(address_map &map) +{ + map.unmap_value_high(); + // 00-FF is for various devices. + map(0x0000, 0x0003).rw("acia1", FUNC(mos6551_device::read), FUNC(mos6551_device::write)); + map(0x0004, 0x0007).rw("acia2", FUNC(mos6551_device::read), FUNC(mos6551_device::write)); + map(0x00f0, 0x00f7).ram(); // for now + //map(0x00f0, 0x00f0).r(m_fdc, FUNC(upd765a_device::msr_r)); + map(0x00ff, 0x00ff).rw(FUNC(d6809_state::term_r), FUNC(d6809_state::term_w)); + map(0x0200, 0x0201).mirror(0xfe).m(m_fdc, FUNC(upd765a_device::map)); + map(0x0300, 0x0300).mirror(0xff).lw8(NAME([this] (u8 data){ m_fdc->tc_w(1); m_fdc->tc_w(0); })); + map(0x1000, 0xdfff).ram(); + map(0xe000, 0xffff).rom().region("roms", 0); +} + + +/* Input ports */ +static INPUT_PORTS_START( d6809 ) +INPUT_PORTS_END + + +void d6809_state::kbd_put(u8 data) +{ + m_term_data = data; +} + +void d6809_state::machine_start() +{ + save_item(NAME(m_term_data)); +} + +void d6809_state::machine_reset() +{ + m_fdc->set_ready_line_connected(1); + m_fdc->set_unscaled_clock(8_MHz_XTAL / 2); // 4MHz for minifloppy + floppy_image_device *floppy = m_floppy0->get_device(); + m_fdc->set_floppy(floppy); + floppy->mon_w(0); +} + +static void floppies(device_slot_interface &device) +{ + device.option_add("525qd", FLOPPY_525_QD); +} + + +void d6809_state::d6809(machine_config &config) +{ + /* basic machine hardware */ + MC6809E(config, m_maincpu, XTAL(14'745'600) / 8); // MC68B09EP + m_maincpu->set_addrmap(AS_PROGRAM, &d6809_state::mem_map); + + MOS6551(config, "acia1", XTAL(14'745'600) / 8); // uses Q clock + MOS6551(config, "acia2", XTAL(14'745'600) / 8); // uses Q clock + + /* video hardware */ + GENERIC_TERMINAL(config, m_terminal, 0); + m_terminal->set_keyboard_callback(FUNC(d6809_state::kbd_put)); + + // Floppy + UPD765A(config, m_fdc, 8'000'000, true, true); + //m_fdc->drq_wr_callback().set(m_fdc, FUNC(upd765a_device::dack_w)); // pin not emulated + FLOPPY_CONNECTOR(config, "fdc:0", floppies, "525qd", floppy_image_device::default_mfm_floppy_formats).enable_sound(true); +} + +/* ROM definition */ +ROM_START( d6809 ) + ROM_REGION( 0x2000, "roms", 0 ) + ROM_LOAD( "d6809.rom", 0x0000, 0x2000, CRC(2ceb40b8) SHA1(780111541234b4f0f781a118d955df61daa56e7e)) +ROM_END + +} // anonymous namespace + + +/* Driver */ + +// YEAR NAME PARENT COMPAT MACHINE INPUT CLASS INIT COMPANY FULLNAME FLAGS +COMP( 1983, d6809, 0, 0, d6809, d6809, d6809_state, empty_init, "Dunfield", "6809 Portable", MACHINE_NOT_WORKING | MACHINE_NO_SOUND_HW | MACHINE_SUPPORTS_SAVE ) |