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Diffstat (limited to 'src/mess/drivers/excali64.c')
-rw-r--r--src/mess/drivers/excali64.c117
1 files changed, 95 insertions, 22 deletions
diff --git a/src/mess/drivers/excali64.c b/src/mess/drivers/excali64.c
index 15f3467a51e..5d3e9dac676 100644
--- a/src/mess/drivers/excali64.c
+++ b/src/mess/drivers/excali64.c
@@ -3,6 +3,7 @@
/***************************************************************************
Excalibur 64 kit computer, designed and sold in Australia by BGR Computers.
+The official schematics have a LOT of errors and omissions.
Skeleton driver created on 2014-12-09.
@@ -15,16 +16,15 @@ ToDo:
- Some keys can be connected to more than one position in the matrix. Need to
determine the correct positions.
- The position of the "Line Insert" key is unknown.
-- PCGEN command not working.
- Colours are approximate.
- Disk controller
-- Banking
+- ROM banking
- The schematic shows the audio counter connected to 2MHz, but this produces
sounds that are too high. Connected to 1MHz for now.
- Serial
- Parallel / Centronics
- Need software
-- Pasting can drop a character or two at the start of a line.
+- Pasting can sometimes drop a character.
****************************************************************************/
@@ -61,16 +61,16 @@ public:
DECLARE_READ8_MEMBER(port00_r);
DECLARE_READ8_MEMBER(port50_r);
DECLARE_WRITE8_MEMBER(port70_w);
- DECLARE_WRITE8_MEMBER(video_w);
MC6845_UPDATE_ROW(update_row);
DECLARE_WRITE_LINE_MEMBER(crtc_de);
DECLARE_WRITE_LINE_MEMBER(crtc_vs);
-
+ DECLARE_MACHINE_RESET(excali64);
required_device<palette_device> m_palette;
private:
const UINT8 *m_p_chargen;
UINT8 *m_p_videoram;
+ UINT8 *m_p_hiresram;
UINT8 m_sys_status;
UINT8 m_kbdrow;
bool m_crtc_vs;
@@ -82,9 +82,11 @@ private:
};
static ADDRESS_MAP_START(excali64_mem, AS_PROGRAM, 8, excali64_state)
- AM_RANGE(0x0000, 0x1FFF) AM_ROM
- AM_RANGE(0x2000, 0x3FFF) AM_ROM AM_WRITE(video_w)
- AM_RANGE(0x4000, 0xFFFF) AM_RAM
+ AM_RANGE(0x0000, 0x1FFF) AM_READ_BANK("bankr1") AM_WRITE_BANK("bankw1")
+ AM_RANGE(0x2000, 0x2FFF) AM_READ_BANK("bankr2") AM_WRITE_BANK("bankw2")
+ AM_RANGE(0x3000, 0x3FFF) AM_READ_BANK("bankr3") AM_WRITE_BANK("bankw3")
+ AM_RANGE(0x4000, 0x4FFF) AM_READ_BANK("bankr4") AM_WRITE_BANK("bankw4")
+ AM_RANGE(0x5000, 0xFFFF) AM_RAM AM_REGION("rambank", 0x5000)
ADDRESS_MAP_END
static ADDRESS_MAP_START(excali64_io, AS_IO, 8, excali64_state)
@@ -101,7 +103,7 @@ static ADDRESS_MAP_START(excali64_io, AS_IO, 8, excali64_state)
ADDRESS_MAP_END
-/* Input ports */
+// Keyboard matrix is not included in schematics, so some guesswork
static INPUT_PORTS_START( excali64 )
PORT_START("KEY.0") /* line 0 */
PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("R") PORT_CODE(KEYCODE_R) PORT_CHAR('r') PORT_CHAR('R') PORT_CHAR(0x12)
@@ -218,30 +220,75 @@ READ8_MEMBER( excali64_state::port00_r )
d0 : /rom ; screen
d1 : ram on
d2 : /low ; high res
-d3 : dispen
+d3 : 2nd colour set (previously, dispen, which is a mistake in hardware and schematic)
d4 : vsync
+d5 : rombank
*/
READ8_MEMBER( excali64_state::port50_r )
{
UINT8 data = m_sys_status & 0x2f;
data |= (UINT8)m_crtc_vs << 4;
- //data |= (UINT8)m_crtc_de << 3; this is a hardware mistake, recommended to disconnect
return data;
}
/*
-d0,1,2 : same as port50
-d3 : 2nd colour set (schematic wrongly says d7)
+d0,1,2,3,5 : same as port50
+(schematic wrongly says d7 used for 2nd colour set)
*/
WRITE8_MEMBER( excali64_state::port70_w )
{
m_sys_status = data;
m_crtc->set_unscaled_clock(BIT(data, 2) ? 2e6 : 1e6);
+ if BIT(data, 1)
+ {
+ // select 64k ram
+ membank("bankr1")->set_entry(0);
+ membank("bankr2")->set_entry(0);
+ membank("bankr3")->set_entry(0);
+ membank("bankr4")->set_entry(0);
+ membank("bankw1")->set_entry(0);
+ membank("bankw2")->set_entry(0);
+ membank("bankw3")->set_entry(0);
+ membank("bankw4")->set_entry(0);
+ }
+ else
+ if BIT(data, 0)
+ {
+ // select videoram and hiresram for writing, and ROM for reading
+ membank("bankr1")->set_entry(1);
+ membank("bankr2")->set_entry(1);
+ membank("bankr3")->set_entry(1);
+ membank("bankr4")->set_entry(0);
+ membank("bankw1")->set_entry(0);
+ membank("bankw2")->set_entry(2);
+ membank("bankw3")->set_entry(2);
+ membank("bankw4")->set_entry(2);
+ }
+ else
+ {
+ // as above, except 4000-4FFF is main ram
+ membank("bankr1")->set_entry(1);
+ membank("bankr2")->set_entry(1);
+ membank("bankr3")->set_entry(1);
+ membank("bankr4")->set_entry(0);
+ membank("bankw1")->set_entry(0);
+ membank("bankw2")->set_entry(2);
+ membank("bankw3")->set_entry(2);
+ membank("bankw4")->set_entry(0);
+ }
}
-WRITE8_MEMBER( excali64_state::video_w )
+MACHINE_RESET_MEMBER( excali64_state, excali64 )
{
- m_p_videoram[offset] = data;
+ membank("bankr1")->set_entry(1); // read from ROM
+ membank("bankr2")->set_entry(1); // read from ROM
+ membank("bankr3")->set_entry(1); // read from ROM
+ membank("bankr4")->set_entry(0); // read from RAM
+ membank("bankw1")->set_entry(0); // write to RAM
+ membank("bankw2")->set_entry(2); // write to videoram
+ membank("bankw3")->set_entry(2); // write to hiresram
+ membank("bankw4")->set_entry(0); // write to RAM
+ m_maincpu->reset();
}
WRITE_LINE_MEMBER( excali64_state::crtc_de )
@@ -280,7 +327,31 @@ PALETTE_INIT_MEMBER( excali64_state, excali64 )
// do this here because driver_init hasn't run yet
m_p_videoram = memregion("videoram")->base();
m_p_chargen = memregion("chargen")->base();
-
+ m_p_hiresram = memregion("hiresram")->base();
+ UINT8 *main = memregion("roms")->base();
+ UINT8 *ram = memregion("rambank")->base();
+
+ // main ram (cp/m mode)
+ membank("bankr1")->configure_entry(0, &ram[0x0000]);
+ membank("bankr2")->configure_entry(0, &ram[0x2000]);
+ membank("bankr3")->configure_entry(0, &ram[0x3000]);
+ membank("bankr4")->configure_entry(0, &ram[0x4000]);//boot
+ membank("bankw1")->configure_entry(0, &ram[0x0000]);//boot
+ membank("bankw2")->configure_entry(0, &ram[0x2000]);
+ membank("bankw3")->configure_entry(0, &ram[0x3000]);
+ membank("bankw4")->configure_entry(0, &ram[0x4000]);//boot
+ // rom_1
+ membank("bankr1")->configure_entry(1, &main[0x0000]);//boot
+ // rom_2
+ membank("bankr2")->configure_entry(1, &main[0x4000]);//boot
+ membank("bankr3")->configure_entry(1, &main[0x5000]);//boot
+ // videoram
+ membank("bankw2")->configure_entry(2, &m_p_videoram[0x0000]);//boot
+ // hiresram
+ membank("bankw3")->configure_entry(2, &m_p_hiresram[0x0000]);//boot
+ membank("bankw4")->configure_entry(2, &m_p_hiresram[0x0000]);
+
+ // Set up foreground palettes
UINT8 r,g,b,i,code;
for (i = 0; i < 32; i++)
{
@@ -291,7 +362,6 @@ PALETTE_INIT_MEMBER( excali64_state, excali64 )
palette.set_pen_color(i, r, g, b);
}
-
// Background
palette.set_pen_color(32, 0x00, 0x00, 0x00); // 0 Black
palette.set_pen_color(33, 0xff, 0x00, 0x00); // 1 Red
@@ -301,7 +371,6 @@ PALETTE_INIT_MEMBER( excali64_state, excali64 )
palette.set_pen_color(37, 0xff, 0xff, 0x00); // 5 Yellow
palette.set_pen_color(38, 0x00, 0xff, 0xff); // 6 Cyan
palette.set_pen_color(39, 0xff, 0xff, 0xff); // 7 White
-
}
MC6845_UPDATE_ROW( excali64_state::update_row )
@@ -321,7 +390,7 @@ MC6845_UPDATE_ROW( excali64_state::update_row )
bg = 32 + ((col >> 1) & 7);
if (BIT(col, 0) & BIT(chr, 7))
- gfx = m_p_videoram[0x800 + (chr<<4) + ra]; // hires definition
+ gfx = m_p_hiresram[(chr<<4) | ra]; // hires definition
else
gfx = m_p_chargen[(chr<<4) | ra]; // normal character
@@ -345,6 +414,8 @@ static MACHINE_CONFIG_START( excali64, excali64_state )
MCFG_CPU_PROGRAM_MAP(excali64_mem)
MCFG_CPU_IO_MAP(excali64_io)
+ MCFG_MACHINE_RESET_OVERRIDE(excali64_state, excali64)
+
MCFG_DEVICE_ADD("uart", I8251, 0)
//MCFG_I8251_TXD_HANDLER(DEVWRITELINE("rs232", rs232_port_device, write_txd))
//MCFG_I8251_RTS_HANDLER(DEVWRITELINE("rs232", rs232_port_device, write_rts))
@@ -398,16 +469,18 @@ static MACHINE_CONFIG_START( excali64, excali64_state )
/* ROM definition */
ROM_START( excali64 )
- ROM_REGION(0x10000, "maincpu", 0)
+ ROM_REGION(0x6000, "roms", 0)
ROM_LOAD( "rom_1.ic17", 0x0000, 0x4000, CRC(e129a305) SHA1(e43ec7d040c2b2e548d22fd6bbc7df8b45a26e5a) )
- ROM_LOAD( "rom_2.ic24", 0x2000, 0x2000, CRC(916d9f5a) SHA1(91c527cce963481b7bebf077e955ca89578bb553) )
+ ROM_LOAD( "rom_2.ic24", 0x4000, 0x2000, CRC(916d9f5a) SHA1(91c527cce963481b7bebf077e955ca89578bb553) )
// fix a bug that causes screen to be filled with 'p'
ROM_FILL(0x4ee, 1, 0)
ROM_FILL(0x4ef, 1, 8)
ROM_FILL(0x4f6, 1, 0)
ROM_FILL(0x4f7, 1, 8)
- ROM_REGION(0x2000, "videoram", ROMREGION_ERASE00)
+ ROM_REGION(0x10000, "rambank", ROMREGION_ERASE00)
+ ROM_REGION(0x1000, "videoram", ROMREGION_ERASE00)
+ ROM_REGION(0x1000, "hiresram", ROMREGION_ERASE00)
ROM_REGION(0x1020, "chargen", 0)
ROM_LOAD( "genex_3.ic43", 0x0000, 0x1000, CRC(b91619a9) SHA1(2ced636cb7b94ba9d329868d7ecf79963cefe9d9) )