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-rw-r--r--src/mame/drivers/vt520.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/src/mame/drivers/vt520.c b/src/mame/drivers/vt520.c
new file mode 100644
index 00000000000..9f4b0216587
--- /dev/null
+++ b/src/mame/drivers/vt520.c
@@ -0,0 +1,111 @@
+// license:BSD-3-Clause
+// copyright-holders:Miodrag Milanovic, Jonathan Gevaryahu
+/***************************************************************************
+
+ DEC VT520
+
+ 02/07/2009 Skeleton driver.
+
+****************************************************************************/
+
+#include "emu.h"
+#include "machine/ram.h"
+#include "cpu/mcs51/mcs51.h"
+
+
+class vt520_state : public driver_device
+{
+public:
+ vt520_state(const machine_config &mconfig, device_type type, const char *tag)
+ : driver_device(mconfig, type, tag) ,
+ m_maincpu(*this, "maincpu") { }
+
+ DECLARE_READ8_MEMBER(vt520_some_r);
+ virtual void machine_reset();
+ virtual void video_start();
+ UINT32 screen_update_vt520(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+ required_device<cpu_device> m_maincpu;
+};
+
+
+static ADDRESS_MAP_START(vt520_mem, AS_PROGRAM, 8, vt520_state)
+ AM_RANGE(0x0000, 0xffff) AM_RAMBANK("bank1")
+ADDRESS_MAP_END
+
+/*
+ On the board there is TC160G41AF (1222) custom chip
+ doing probably all video/uart logic
+ there is 43.430MHz xtal near by
+*/
+
+READ8_MEMBER( vt520_state::vt520_some_r )
+{
+ //bit 5 0
+ //bit 6 1
+ return 0x40;
+}
+
+static ADDRESS_MAP_START(vt520_io, AS_IO, 8, vt520_state)
+ ADDRESS_MAP_UNMAP_HIGH
+ AM_RANGE(0x7ffb, 0x7ffb) AM_READ(vt520_some_r)
+ADDRESS_MAP_END
+
+/* Input ports */
+static INPUT_PORTS_START( vt520 )
+INPUT_PORTS_END
+
+
+void vt520_state::machine_reset()
+{
+ address_space &space = m_maincpu->space(AS_PROGRAM);
+ UINT8 *rom = memregion("maincpu")->base();
+ space.unmap_write(0x0000, 0xffff);
+ membank("bank1")->set_base(rom + 0x70000);
+}
+
+void vt520_state::video_start()
+{
+}
+
+UINT32 vt520_state::screen_update_vt520(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
+{
+ return 0;
+}
+
+static MACHINE_CONFIG_START( vt520, vt520_state )
+ /* basic machine hardware */
+ MCFG_CPU_ADD("maincpu",I8032, XTAL_20MHz)
+ MCFG_CPU_PROGRAM_MAP(vt520_mem)
+ MCFG_CPU_IO_MAP(vt520_io)
+
+
+ /* video hardware */
+ MCFG_SCREEN_ADD("screen", RASTER)
+ MCFG_SCREEN_REFRESH_RATE(50)
+ MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) /* not accurate */
+ MCFG_SCREEN_SIZE(802, 480)
+ MCFG_SCREEN_VISIBLE_AREA(0, 802-1, 0, 480-1)
+ MCFG_SCREEN_UPDATE_DRIVER(vt520_state, screen_update_vt520)
+ MCFG_SCREEN_PALETTE("palette")
+
+ MCFG_PALETTE_ADD_BLACK_AND_WHITE("palette")
+
+ // On the board there are two M5M44256BJ-7 chips
+ // Which are DRAM 256K x 4bit
+ /* internal ram */
+ MCFG_RAM_ADD(RAM_TAG)
+ MCFG_RAM_DEFAULT_SIZE("256K")
+MACHINE_CONFIG_END
+
+/* ROM definition */
+ROM_START( vt520 )
+ ROM_REGION( 0x80000, "maincpu", ROMREGION_ERASEFF )
+ 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
+ROM_END
+
+/* Driver */
+
+/* YEAR NAME PARENT COMPAT MACHINE INPUT INIT COMPANY FULLNAME FLAGS */
+//COMP( 1993, vt510, 0, 0, vt520, vt520, driver_device, 0, "Digital Equipment Corporation", "VT510", MACHINE_NOT_WORKING)
+COMP( 1994, vt520, 0, 0, vt520, vt520, driver_device, 0, "Digital Equipment Corporation", "VT520", MACHINE_NOT_WORKING | MACHINE_NO_SOUND)
+//COMP( 1994, vt525, 0, 0, vt520, vt520, driver_device, 0, "Digital Equipment Corporation", "VT525", MACHINE_NOT_WORKING)