summaryrefslogtreecommitdiffstatshomepage
path: root/src/mess/drivers/a6809.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/mess/drivers/a6809.c')
-rw-r--r--src/mess/drivers/a6809.c277
1 files changed, 0 insertions, 277 deletions
diff --git a/src/mess/drivers/a6809.c b/src/mess/drivers/a6809.c
deleted file mode 100644
index 38a455614ca..00000000000
--- a/src/mess/drivers/a6809.c
+++ /dev/null
@@ -1,277 +0,0 @@
-// license:BSD-3-Clause
-// copyright-holders:Robbbert and unknown others
-/***************************************************************************
-
- Acorn 6809
-
- 2009-05-12 Skeleton driver.
- 2013-12-16 Fixed video [Robbbert]
-
- Acorn System 3 update?
- http://acorn.chriswhy.co.uk/8bit_Upgrades/Acorn_6809_CPU.html
-
- This is a few boards emulated together:
- - 6809 main board
- - 80x25 video board
- - FDC board (to come)
-
-The video board has a mc6845, and the characters do not go to a character
-generator, instead they go to a SAA5050, which has its own CG inbuilt, plus
-many other features.
-
-ToDo:
- - FDC (address A00)
- - Centronics Printer (VIA port A)
-
-Commands:
-C - Echo to printer ( C '+' turns it on)
-D - boot from disk
-G - Go
-L - Load tape
-P - Run from pc reg
-R - Display regs
-S - Save tape
-T - Trace
-V - Set breakpoint
-
-M - Modify memory
-MV - Modify memory at breakpoint address
-MG - Modify memory from Go address
-MP - Modify memory from pc-reg address
-MR - Modify regs
-
-While modifying memory:
-, show next address
-- show previous address
-enter show next address
-; exit
-
-
-****************************************************************************/
-
-#include "emu.h"
-#include "cpu/m6809/m6809.h"
-#include "machine/6522via.h"
-#include "machine/keyboard.h"
-#include "video/saa5050.h"
-#include "video/mc6845.h"
-#include "imagedev/cassette.h"
-#include "sound/wave.h"
-
-
-class a6809_state : public driver_device
-{
-public:
- a6809_state(const machine_config &mconfig, device_type type, const char *tag)
- : driver_device(mconfig, type, tag)
- , m_p_videoram(*this, "videoram")
- , m_via(*this, "via")
- , m_cass(*this, "cassette")
- , m_maincpu(*this, "maincpu")
- , m_crtc(*this, "mc6845")
- { }
-
- DECLARE_WRITE8_MEMBER(kbd_put);
- DECLARE_READ8_MEMBER(videoram_r);
- DECLARE_WRITE8_MEMBER(a6809_address_w);
- DECLARE_WRITE8_MEMBER(a6809_register_w);
- DECLARE_WRITE_LINE_MEMBER(cass_w);
- DECLARE_MACHINE_RESET(a6809);
- TIMER_DEVICE_CALLBACK_MEMBER(a6809_c);
- TIMER_DEVICE_CALLBACK_MEMBER(a6809_p);
- required_shared_ptr<UINT8> m_p_videoram;
- UINT16 m_start_address;
- UINT16 m_cursor_address;
-private:
- UINT8 m_cass_data[4];
- bool m_cass_state;
- bool m_cassold;
- UINT8 m_video_index;
- required_device<via6522_device> m_via;
- required_device<cassette_image_device> m_cass;
- required_device<cpu_device> m_maincpu;
- required_device<mc6845_device> m_crtc;
-};
-
-
-static ADDRESS_MAP_START(a6809_mem, AS_PROGRAM, 8, a6809_state)
- ADDRESS_MAP_UNMAP_HIGH
- AM_RANGE(0x0000,0x03ff) AM_RAM
- AM_RANGE(0x0400,0x07ff) AM_RAM AM_SHARE("videoram")
- AM_RANGE(0x0800,0x0800) AM_DEVREAD("mc6845", mc6845_device, status_r) AM_WRITE(a6809_address_w)
- AM_RANGE(0x0801,0x0801) AM_DEVREAD("mc6845", mc6845_device, register_r) AM_WRITE(a6809_register_w)
- AM_RANGE(0x0900,0x090f) AM_MIRROR(0xf0) AM_DEVREADWRITE("via", via6522_device, read, write)
- AM_RANGE(0xf000,0xf7ff) // optional ROM
- AM_RANGE(0xf800,0xffff) AM_ROM AM_REGION("maincpu", 0)
-ADDRESS_MAP_END
-
-static ADDRESS_MAP_START( a6809_io, AS_IO, 8, a6809_state)
- ADDRESS_MAP_UNMAP_HIGH
-ADDRESS_MAP_END
-
-/* Input ports */
-static INPUT_PORTS_START( a6809 )
-INPUT_PORTS_END
-
-
-MACHINE_RESET_MEMBER( a6809_state, a6809)
-{
- m_via->write_pb0(0);
- m_via->write_pb1(0);
- m_via->write_pb2(0);
- m_via->write_pb3(0);
- m_via->write_pb4(0);
- m_via->write_pb5(0);
- m_via->write_pb6(0);
- m_via->write_pb7(0);
-}
-
-READ8_MEMBER( a6809_state::videoram_r )
-{
- offset += m_start_address;
-
- if (m_cursor_address == offset)
- return 0x7f; // cheap cursor
- else
- return m_p_videoram[offset&0x3ff];
-}
-
-WRITE8_MEMBER( a6809_state::a6809_address_w )
-{
- m_crtc->address_w( space, 0, data );
-
- m_video_index = data & 0x1f;
-}
-
-WRITE8_MEMBER( a6809_state::a6809_register_w )
-{
- UINT16 temp = m_start_address;
- UINT16 temq = m_cursor_address;
-
- // data is 18, but we need 19, to give the 20 rows needed by the SAA5050
- if (m_video_index == 9)
- data++;
-
- m_crtc->register_w( space, 0, data );
-
- // Get start address
- if (m_video_index == 12)
- m_start_address = ((data & 7) << 8 ) | (temp & 0xff);
- else
- if (m_video_index == 13)
- m_start_address = data | (temp & 0x3f00);
-
- else
- // Get cursor address
- if (m_video_index == 14)
- m_cursor_address = ((data & 7) << 8 ) | (temq & 0xff);
- else
- if (m_video_index == 15)
- m_cursor_address = data | (temq & 0x3f00);
-}
-
-WRITE_LINE_MEMBER( a6809_state::cass_w )
-{
- m_cass_state = state;
-}
-
-TIMER_DEVICE_CALLBACK_MEMBER(a6809_state::a6809_c)
-{
- m_cass_data[3]++;
-
- if (m_cass_state != m_cassold)
- {
- m_cass_data[3] = 0;
- m_cassold = m_cass_state;
- }
-
- if (m_cass_state)
- m_cass->output(BIT(m_cass_data[3], 0) ? -1.0 : +1.0); // 2400Hz
- else
- m_cass->output(BIT(m_cass_data[3], 1) ? -1.0 : +1.0); // 1200Hz
-}
-
-TIMER_DEVICE_CALLBACK_MEMBER(a6809_state::a6809_p)
-{
- /* cassette - turn 1200/2400Hz to a bit */
- m_cass_data[1]++;
- UINT8 cass_ws = (m_cass->input() > +0.03) ? 1 : 0;
-
- if (cass_ws != m_cass_data[0])
- {
- m_cass_data[0] = cass_ws;
- m_via->write_pb7(m_cass_data[1] < 12);
- m_cass_data[1] = 0;
- }
-}
-
-WRITE8_MEMBER( a6809_state::kbd_put )
-{
- UINT8 d = data & 0x7f;
- if (d == 8) d = 0x7f; // allow backspace to work
-
- m_via->write_pb0((d>>0)&1);
- m_via->write_pb1((d>>1)&1);
- m_via->write_pb2((d>>2)&1);
- m_via->write_pb3((d>>3)&1);
- m_via->write_pb4((d>>4)&1);
- m_via->write_pb5((d>>5)&1);
- m_via->write_pb6((d>>6)&1);
- m_via->write_cb1(1);
- m_via->write_cb1(0);
-}
-
-static MACHINE_CONFIG_START( a6809, a6809_state )
- /* basic machine hardware */
- MCFG_CPU_ADD("maincpu",M6809E, XTAL_4MHz)
- MCFG_CPU_PROGRAM_MAP(a6809_mem)
- MCFG_CPU_IO_MAP(a6809_io)
- MCFG_MACHINE_RESET_OVERRIDE(a6809_state, a6809)
-
- /* video hardware */
- MCFG_SCREEN_ADD("screen", RASTER)
- MCFG_SCREEN_REFRESH_RATE(50)
- MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500))
- MCFG_SCREEN_SIZE(40 * 12, 25 * 20)
- MCFG_SCREEN_VISIBLE_AREA(0, 40 * 12 - 1, 0, 25 * 20 - 1)
- MCFG_SCREEN_UPDATE_DEVICE("saa5050", saa5050_device, screen_update)
- MCFG_PALETTE_ADD("palette", 8)
-
- /* sound hardware */
- MCFG_SPEAKER_STANDARD_MONO("mono")
- MCFG_SOUND_WAVE_ADD(WAVE_TAG, "cassette")
- MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.25)
-
- /* Devices */
- MCFG_DEVICE_ADD("via", VIA6522, XTAL_4MHz / 4)
- MCFG_VIA6522_CB2_HANDLER(WRITELINE(a6809_state, cass_w))
- MCFG_VIA6522_IRQ_HANDLER(DEVWRITELINE("maincpu", m6809e_device, irq_line))
-
- MCFG_MC6845_ADD("mc6845", MC6845, "screen", XTAL_4MHz / 2)
- MCFG_MC6845_SHOW_BORDER_AREA(false)
- MCFG_MC6845_CHAR_WIDTH(12)
-
- MCFG_DEVICE_ADD("saa5050", SAA5050, 6000000)
- MCFG_SAA5050_D_CALLBACK(READ8(a6809_state, videoram_r))
- MCFG_SAA5050_SCREEN_SIZE(40, 25, 40)
-
- MCFG_DEVICE_ADD("keyboard", GENERIC_KEYBOARD, 0)
- MCFG_GENERIC_KEYBOARD_CB(WRITE8(a6809_state, kbd_put))
- MCFG_CASSETTE_ADD( "cassette" )
- MCFG_TIMER_DRIVER_ADD_PERIODIC("a6809_c", a6809_state, a6809_c, attotime::from_hz(4800))
- MCFG_TIMER_DRIVER_ADD_PERIODIC("a6809_p", a6809_state, a6809_p, attotime::from_hz(40000))
-MACHINE_CONFIG_END
-
-/* ROM definition */
-ROM_START( a6809 )
- ROM_REGION( 0x800, "maincpu", 0 )
- ROM_LOAD( "acorn6809.bin", 0x000, 0x800, CRC(5fa5b632) SHA1(b14a884bf82a7a8c23bc03c2e112728dd1a74896) )
-
- ROM_REGION( 0x100, "proms", 0 )
- ROM_LOAD( "acorn6809.ic11", 0x0000, 0x0100, CRC(7908317d) SHA1(e0f1e5bd3a8598d3b62bc432dd1f3892ed7e66d8) ) // address decoder
-ROM_END
-
-/* Driver */
-
-/* YEAR NAME PARENT COMPAT MACHINE INPUT CLASS INIT COMPANY FULLNAME FLAGS */
-COMP( 1980, a6809, 0, 0, a6809, a6809, driver_device, 0, "Acorn", "System 3 (6809 CPU)", 0 )