112 lines
3.3 KiB
C
112 lines
3.3 KiB
C
// license:BSD-3-Clause
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// copyright-holders:Miodrag Milanovic, Jonathan Gevaryahu
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/***************************************************************************
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DEC VT520
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02/07/2009 Skeleton driver.
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****************************************************************************/
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#include "emu.h"
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#include "machine/ram.h"
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#include "cpu/mcs51/mcs51.h"
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class vt520_state : public driver_device
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{
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public:
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vt520_state(const machine_config &mconfig, device_type type, const char *tag)
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: driver_device(mconfig, type, tag) ,
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m_maincpu(*this, "maincpu") { }
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DECLARE_READ8_MEMBER(vt520_some_r);
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virtual void machine_reset();
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virtual void video_start();
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UINT32 screen_update_vt520(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
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required_device<cpu_device> m_maincpu;
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};
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static ADDRESS_MAP_START(vt520_mem, AS_PROGRAM, 8, vt520_state)
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AM_RANGE(0x0000, 0xffff) AM_RAMBANK("bank1")
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ADDRESS_MAP_END
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/*
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On the board there is TC160G41AF (1222) custom chip
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doing probably all video/uart logic
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there is 43.430MHz xtal near by
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*/
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READ8_MEMBER( vt520_state::vt520_some_r )
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{
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//bit 5 0
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//bit 6 1
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return 0x40;
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}
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static ADDRESS_MAP_START(vt520_io, AS_IO, 8, vt520_state)
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ADDRESS_MAP_UNMAP_HIGH
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AM_RANGE(0x7ffb, 0x7ffb) AM_READ(vt520_some_r)
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ADDRESS_MAP_END
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/* Input ports */
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static INPUT_PORTS_START( vt520 )
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INPUT_PORTS_END
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void vt520_state::machine_reset()
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{
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address_space &space = m_maincpu->space(AS_PROGRAM);
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UINT8 *rom = memregion("maincpu")->base();
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space.unmap_write(0x0000, 0xffff);
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membank("bank1")->set_base(rom + 0x70000);
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}
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void vt520_state::video_start()
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{
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}
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UINT32 vt520_state::screen_update_vt520(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
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{
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return 0;
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}
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static MACHINE_CONFIG_START( vt520, vt520_state )
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/* basic machine hardware */
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MCFG_CPU_ADD("maincpu",I8032, XTAL_20MHz)
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MCFG_CPU_PROGRAM_MAP(vt520_mem)
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MCFG_CPU_IO_MAP(vt520_io)
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/* video hardware */
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MCFG_SCREEN_ADD("screen", RASTER)
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MCFG_SCREEN_REFRESH_RATE(50)
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MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) /* not accurate */
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MCFG_SCREEN_SIZE(802, 480)
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MCFG_SCREEN_VISIBLE_AREA(0, 802-1, 0, 480-1)
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MCFG_SCREEN_UPDATE_DRIVER(vt520_state, screen_update_vt520)
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MCFG_SCREEN_PALETTE("palette")
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MCFG_PALETTE_ADD_BLACK_AND_WHITE("palette")
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// On the board there are two M5M44256BJ-7 chips
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// Which are DRAM 256K x 4bit
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/* internal ram */
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MCFG_RAM_ADD(RAM_TAG)
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MCFG_RAM_DEFAULT_SIZE("256K")
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MACHINE_CONFIG_END
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/* ROM definition */
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ROM_START( vt520 )
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ROM_REGION( 0x80000, "maincpu", ROMREGION_ERASEFF )
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ROM_LOAD( "23-010ed-00.e20", 0x0000, 0x80000, CRC(2502cc22) SHA1(0437c3107412f69e09d050fef003f2a81d8a3163)) // "(C)DEC94 23-010ED-00 // 9739 D" dumped from a VT520-A4 model
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ROM_END
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/* Driver */
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/* YEAR NAME PARENT COMPAT MACHINE INPUT INIT COMPANY FULLNAME FLAGS */
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//COMP( 1993, vt510, 0, 0, vt520, vt520, driver_device, 0, "Digital Equipment Corporation", "VT510", GAME_NOT_WORKING)
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COMP( 1994, vt520, 0, 0, vt520, vt520, driver_device, 0, "Digital Equipment Corporation", "VT520", GAME_NOT_WORKING | GAME_NO_SOUND)
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//COMP( 1994, vt525, 0, 0, vt520, vt520, driver_device, 0, "Digital Equipment Corporation", "VT525", GAME_NOT_WORKING)
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