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r36463 Wednesday 18th March, 2015 at 02:04:32 UTC by Alex W. Jackson
a7800.c: Address map corrections and cleanups [Mike Saarna, Alex Jackson]
[src/mess/drivers]a7800.c

trunk/src/mess/drivers/a7800.c
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117117   m_maria(*this, "maria"),
118118   m_io_joysticks(*this, "joysticks"),
119119   m_io_buttons(*this, "buttons"),
120   m_io_vblank(*this, "vblank"),
121120   m_io_console_buttons(*this, "console_buttons"),
122121   m_cart(*this, "cartslot"),
123   m_screen(*this, "screen") { }
122   m_screen(*this, "screen"),
123   m_bios(*this, "maincpu") { }
124124
125125   int m_lines;
126126   int m_ispal;
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132132   int m_p2_one_button;
133133   int m_bios_enabled;
134134
135   UINT8 *m_bios;
136
137135   DECLARE_READ8_MEMBER(bios_or_cart_r);
138136   DECLARE_WRITE8_MEMBER(ram0_w);
139137   DECLARE_READ8_MEMBER(tia_r);
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158156   required_device<atari_maria_device> m_maria;
159157   required_ioport m_io_joysticks;
160158   required_ioport m_io_buttons;
161   required_ioport m_io_vblank;
162159   required_ioport m_io_console_buttons;
163160   required_device<a78_cart_slot_device> m_cart;
164161   required_device<screen_device> m_screen;
162   required_region_ptr<UINT8> m_bios;
165163};
166164
167165
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282280static ADDRESS_MAP_START( a7800_mem, AS_PROGRAM, 8, a7800_state )
283281   AM_RANGE(0x0000, 0x001f) AM_MIRROR(0x300) AM_READWRITE(tia_r, tia_w)
284282   AM_RANGE(0x0020, 0x003f) AM_MIRROR(0x300) AM_DEVREADWRITE("maria", atari_maria_device, read, write)
285   AM_RANGE(0x0040, 0x00ff) AM_RAMBANK("ram0")     // RAM (6116 block 0)
286   AM_RANGE(0x0140, 0x01ff) AM_RAMBANK("ram1")     // RAM (6116 block 1)
283   AM_RANGE(0x0040, 0x00ff) AM_RAMBANK("zpmirror") // mirror of 0x2040-0x20ff, for zero page
284   AM_RANGE(0x0140, 0x01ff) AM_RAMBANK("spmirror") // mirror of 0x2140-0x21ff, for stack page
287285   AM_RANGE(0x0280, 0x02ff) AM_DEVREADWRITE("riot", riot6532_device, read, write)
288   AM_RANGE(0x0480, 0x04ff) AM_MIRROR(0x100) AM_RAMBANK("riot_ram")
289   AM_RANGE(0x1800, 0x27ff) AM_RAMBANK("main_ram")
290
291   AM_RANGE(0x2040, 0x20ff) AM_RAMBANK("ram0")     // mirror (6116 block 0)
292   AM_RANGE(0x2140, 0x21ff) AM_RAMBANK("ram1")     // mirror (6116 block 1)
293
294   AM_RANGE(0x2800, 0x2fff) AM_RAMBANK("mirror")   // these should mirror "main_ram" (according to docs)
295   AM_RANGE(0x3000, 0x37ff) AM_RAMBANK("mirror")   // but system have issues in such case...
296   AM_RANGE(0x3800, 0x3fff) AM_RAMBANK("mirror")
286   AM_RANGE(0x0480, 0x04ff) AM_RAM AM_SHARE("riot_ram") AM_MIRROR(0x100)
287   AM_RANGE(0x1800, 0x1fff) AM_RAM AM_SHARE("6116_1")
288   AM_RANGE(0x2000, 0x27ff) AM_RAM AM_SHARE("6116_2") AM_MIRROR(0x0800)
289                             // According to the official Software Guide, the RAM at 0x2000 is
290                             // repeatedly mirrored up to 0x3fff, but this is evidently incorrect
291                             // because the High Score Cartridge maps ROM at 0x3000-0x3fff
292                             // Hardware tests show that only the mirror at 0x2800-0x2fff actually
293                             // exists, and only on some hardware (MARIA? motherboard?) revisions
297294   AM_RANGE(0x4000, 0xffff) AM_DEVWRITE("cartslot", a78_cart_slot_device, write_40xx)
298295   AM_RANGE(0x4000, 0xbfff) AM_DEVREAD("cartslot", a78_cart_slot_device, read_40xx)
299296   AM_RANGE(0xc000, 0xffff) AM_READ(bios_or_cart_r)    // here also the BIOS can be accessed
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322319   PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_BUTTON1)       PORT_PLAYER(1)
323320   PORT_BIT(0xF0, IP_ACTIVE_LOW, IPT_UNUSED)
324321
325   PORT_START("vblank")
326   PORT_BIT(0x7F, IP_ACTIVE_LOW, IPT_UNUSED)
327   PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_CUSTOM) PORT_VBLANK("screen")
328
329322   PORT_START("console_buttons")
330323   PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_OTHER)  PORT_NAME("Reset")         PORT_CODE(KEYCODE_R)
331324   PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_OTHER)  PORT_NAME("Select")        PORT_CODE(KEYCODE_S)
r244974r244975
13061299
13071300void a7800_state::machine_start()
13081301{
1309   m_bios = machine().root_device().memregion("maincpu")->base() + 0xc000;
13101302   save_item(NAME(m_p1_one_button));
13111303   save_item(NAME(m_p2_one_button));
13121304   save_item(NAME(m_bios_enabled));
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13141306   save_item(NAME(m_ctrl_reg));
13151307   save_item(NAME(m_maria_flag));
13161308
1309   // set up RAM mirrors
1310   UINT8 *ram = reinterpret_cast<UINT8 *>(memshare("6116_2")->ptr());
1311   membank("zpmirror")->set_base(ram + 0x0040);
1312   membank("spmirror")->set_base(ram + 0x0140);
1313
13171314   // install additional handlers, if needed
13181315   if (m_cart->exists())
13191316   {
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14201417***************************************************************************/
14211418
14221419ROM_START( a7800 )
1423   ROM_REGION(0x10000, "maincpu", ROMREGION_ERASEFF)
1420   ROM_REGION(0x4000, "maincpu", ROMREGION_ERASEFF)
14241421   ROM_SYSTEM_BIOS( 0, "a7800", "Atari 7800" )
1425   ROMX_LOAD("7800.u7", 0xf000, 0x1000, CRC(5d13730c) SHA1(d9d134bb6b36907c615a594cc7688f7bfcef5b43), ROM_BIOS(1))
1422   ROMX_LOAD("7800.u7", 0x3000, 0x1000, CRC(5d13730c) SHA1(d9d134bb6b36907c615a594cc7688f7bfcef5b43), ROM_BIOS(1))
14261423   ROM_SYSTEM_BIOS( 1, "a7800pr", "Atari 7800 (prototype with Asteroids)" )
1427   ROMX_LOAD("c300558-001a.u7", 0xc000, 0x4000, CRC(a0e10edf) SHA1(14584b1eafe9721804782d4b1ac3a4a7313e455f), ROM_BIOS(2))
1424   ROMX_LOAD("c300558-001a.u7", 0x0000, 0x4000, CRC(a0e10edf) SHA1(14584b1eafe9721804782d4b1ac3a4a7313e455f), ROM_BIOS(2))
14281425ROM_END
14291426
14301427ROM_START( a7800p )
1431   ROM_REGION(0x10000, "maincpu", ROMREGION_ERASEFF)
1432   ROM_LOAD("7800pal.rom", 0xc000, 0x4000, CRC(d5b61170) SHA1(5a140136a16d1d83e4ff32a19409ca376a8df874))
1428   ROM_REGION(0x4000, "maincpu", ROMREGION_ERASEFF)
1429   ROM_LOAD("7800pal.rom", 0x0000, 0x4000, CRC(d5b61170) SHA1(5a140136a16d1d83e4ff32a19409ca376a8df874))
14331430ROM_END
14341431
14351432

https://github.com/mamedev/mame/commit/474849d17006b667024764047fb8f354549ff55a

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