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// license:BSD-3-Clause
// copyright-holders:Miodrag Milanovic, Jonathan Gevaryahu
/***************************************************************************
DEC VT520
02/07/2009 Skeleton driver.
****************************************************************************/
#include "emu.h"
#include "cpu/mcs51/mcs51.h"
//#include "machine/mc68681.h"
#include "machine/ram.h"
#include "emupal.h"
#include "screen.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"),
m_rom(*this, "maincpu")
{ }
void vt520(machine_config &config);
void vt420(machine_config &config);
private:
uint8_t vt520_some_r();
virtual void machine_reset() override;
virtual void video_start() override;
uint32_t screen_update_vt520(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
required_device<cpu_device> m_maincpu;
required_region_ptr<uint8_t> m_rom;
void vt520_io(address_map &map);
void vt520_mem(address_map &map);
};
void vt520_state::vt520_mem(address_map &map)
{
map(0x0000, 0xffff).bankrw("bank1");
}
/*
On the board there is TC160G41AF (1222) custom chip
doing probably all video/uart logic
there is 43.320MHz xtal near by
*/
uint8_t vt520_state::vt520_some_r()
{
//bit 5 0
//bit 6 1
return 0x40;
}
void vt520_state::vt520_io(address_map &map)
{
map.unmap_value_high();
map(0x7ffb, 0x7ffb).r(FUNC(vt520_state::vt520_some_r));
}
/* Input ports */
static INPUT_PORTS_START( vt520 )
INPUT_PORTS_END
void vt520_state::machine_reset()
{
address_space &space = m_maincpu->space(AS_PROGRAM);
space.unmap_write(0x0000, 0xffff);
membank("bank1")->set_base(&m_rom[m_rom.length() - 0x10000]);
}
void vt520_state::video_start()
{
}
uint32_t vt520_state::screen_update_vt520(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
return 0;
}
void vt520_state::vt420(machine_config &config)
{
/* basic machine hardware */
I80C31(config, m_maincpu, XTAL(43'320'000) / 3); // SCN8031HCFN40 (divider not verified)
m_maincpu->set_addrmap(AS_PROGRAM, &vt520_state::vt520_mem);
m_maincpu->set_addrmap(AS_IO, &vt520_state::vt520_io);
/* video hardware */
screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER));
screen.set_refresh_hz(50);
screen.set_vblank_time(ATTOSECONDS_IN_USEC(2500)); /* not accurate */
screen.set_size(802, 480);
screen.set_visarea(0, 802-1, 0, 480-1);
screen.set_screen_update(FUNC(vt520_state::screen_update_vt520));
screen.set_palette("palette");
PALETTE(config, "palette", palette_device::MONOCHROME);
}
void vt520_state::vt520(machine_config &config)
{
/* basic machine hardware */
I80C32(config, m_maincpu, XTAL(20'000'000)); // Philips P80C32IBPN
m_maincpu->set_addrmap(AS_PROGRAM, &vt520_state::vt520_mem);
m_maincpu->set_addrmap(AS_IO, &vt520_state::vt520_io);
/* video hardware */
screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER));
screen.set_refresh_hz(50);
screen.set_vblank_time(ATTOSECONDS_IN_USEC(2500)); /* not accurate */
screen.set_size(802, 480);
screen.set_visarea(0, 802-1, 0, 480-1);
screen.set_screen_update(FUNC(vt520_state::screen_update_vt520));
screen.set_palette("palette");
PALETTE(config, "palette", palette_device::MONOCHROME);
// On the board there are two M5M44256BJ-7 chips
// Which are DRAM 256K x 4bit
/* internal ram */
RAM(config, RAM_TAG).set_default_size("256K");
}
/**************************************************************************************************************
DEC VT420.
Chips: SCN8031HCFN40, SCN2681TC1N40, M5M4464AP, HM62256LFP-10T, TC23SC070AT, TC531001CP-1815
Crystals: 43.320
***************************************************************************************************************/
ROM_START( vt420 )
ROM_REGION(0x20000, "maincpu", 0)
ROM_SYSTEM_BIOS(0, "v14", "Version 1.4")
ROMX_LOAD( "23-202e9.e2", 0x00000, 0x20000, CRC(ca6cfb18) SHA1(2e0d3c16e04808bc6a45a0fc032b597458e6dd85), ROM_BIOS(0) )
ROM_SYSTEM_BIOS(1, "v13", "Version 1.3")
ROMX_LOAD( "23-068e9-00.e2", 0x00000, 0x20000, CRC(22c3f93b) SHA1(b212911c41e4dba2e09d91fdd1f72d6c7536b0af), ROM_BIOS(1) )
ROM_END
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 */
COMP( 1990, vt420, 0, 0, vt420, vt520, vt520_state, empty_init, "Digital Equipment Corporation", "VT420 Video Terminal", MACHINE_IS_SKELETON )
//COMP( 1993, vt510, 0, 0, vt520, vt520, vt520_state, empty_init, "Digital Equipment Corporation", "VT510 Video Terminal", MACHINE_IS_SKELETON)
COMP( 1994, vt520, 0, 0, vt520, vt520, vt520_state, empty_init, "Digital Equipment Corporation", "VT520 Video Terminal", MACHINE_IS_SKELETON)
//COMP( 1994, vt525, 0, 0, vt520, vt520, vt520_state, empty_init, "Digital Equipment Corporation", "VT525 Video Terminal", MACHINE_IS_SKELETON)
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