Sprinter/mame
2
0
Fork 0
mirror of https://github.com/holub/mame synced 2025-04-23 17:00:53 +03:00
Code Issues Actions 1 Packages Projects Releases Wiki Activity

(MESS) alphatronic : added notes

Browse Source
This commit is contained in:
Robbbert 2014-03-09 12:14:22 +00:00
parent 544b60f82a
commit 3677cd32d9
1 changed files with 30 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
src/mess/drivers/alphatro.c
View File

@ -2,7 +2,7 @@
// copyright-holders:Barry Rodewald, Robbbert
/***************************************************************************
Triumph-Adler's Alphatronic PC
Triumph-Adler (or Royal) Alphatronic PC
skeleton driver
@ -10,20 +10,31 @@
Other chips: 8251, 8257, 8259
Crystals: 16MHz, 17.73447MHz
Floppy format: 2 sides, 40 tracks, 16 sectors, 256 bytes = 320kb.
FDC (unknown) is in a plug-in module.
Floppy format: 13cm, 2 sides, 40 tracks, 16 sectors, 256 bytes = 320kb.
FDC (uPD765) is in a plug-in module, with an undumped rom.
Has a socket for monochrome (to the standard amber monitor),
and another for RGB. We emulate this with a configuration switch.
The Z80 must start at E000, but unlike other designs (Super80 for
example) which cause the ROMs to appear everywhere during boot,
this one (it seems) holds the data bus low until E000 is reached.
This kind of boot still needs to be emulated.
This machine has 64k RAM, the ROMs being copied into RAM when
needed.
There are several mystery ports which might be connected to the floppy
disk system. These are Port 30 (in and out), Port 20 (out) and certain
bits of Port 10 (in). This unit communicates via a simple parallel
interface.
Port 10 bit 6 when high switches A000-DFFF over to roms that are in
a cart which is plugged into the RomPack socket. If C3 is found at
A000 or C000, then a jump is made to that address. It is however
possible that one of these addresses might be for the rom in the
floppy controller unit.
ToDo:
- Fix cassette loading (broke during devcb2 conversion)
- Add fdc, then connect up software list
***************************************************************************/
#include "emu.h"
@ -45,7 +56,6 @@ public:
enum
{
TIMER_SYSTEM,
TIMER_ALPHATRO_BEEP_OFF
};
alphatro_state(const machine_config &mconfig, device_type type, const char *tag)
@ -101,18 +111,11 @@ WRITE8_MEMBER( alphatro_state::port10_w )
// Bit 2 ? after a cload
// Bit 3 -> cassette relay
// Bit 4 -> BEEP
// Bit 6 -> 1 = select ROM pack
UINT16 length = 0;
data &= 0xfe;
if (data == 0x10)
length = 400; // BEEP command
if (length)
{
timer_set(attotime::from_msec(length), TIMER_ALPHATRO_BEEP_OFF);
m_beep->set_state(1);
}
m_beep->set_state(BIT(data, 4));
m_cass->change_state( BIT(data, 3) ? CASSETTE_MOTOR_ENABLED : CASSETTE_MOTOR_DISABLED, CASSETTE_MASK_MOTOR);
@ -127,9 +130,6 @@ void alphatro_state::device_timer(emu_timer &timer, device_timer_id id, int para
case TIMER_SYSTEM:
m_timer_bit ^= 0x80;
break;
case TIMER_ALPHATRO_BEEP_OFF:
m_beep->set_state(0);
break;
default:
assert_always(FALSE, "Unknown id in alphatro_state::device_timer");
}
@ -377,10 +377,12 @@ void alphatro_state::machine_start()
void alphatro_state::machine_reset()
{
// do what the IPL does
UINT8* ROM = memregion("maincpu")->base();
UINT8* ROM = memregion("roms")->base();
m_maincpu->set_pc(0xe000);
memcpy(m_p_ram, ROM, 0xf000); // copy BASIC to RAM, which the undumped IPL is supposed to do.
memcpy(m_p_videoram, ROM+0x1000, 0x1000);
// If BASIC is missing then it boots into the Monitor
memcpy(m_p_ram, ROM, 0x6000); // Copy BASIC to RAM
// Top half of this rom has keyboard tables and appears to be unused
memcpy(m_p_ram+0xe000, ROM+0xe000, 0x1000); // copy BIOS + Monitor to RAM
// probably not correct, exact meaning of port is unknown, vblank/vsync is too slow.
m_sys_timer->adjust(attotime::from_usec(10),0,attotime::from_usec(10));
@ -388,8 +390,8 @@ void alphatro_state::machine_reset()
m_cass_state = 1;
m_cass_data[0] = 0;
m_cass_data[1] = 0;
m_usart->write_rxd(0);
m_cass_data[3] = 0;
m_usart->write_rxd(0);
m_beep->set_state(0);
m_beep->set_frequency(950); /* piezo-device needs to be measured */
}
@ -453,7 +455,7 @@ static const cassette_interface alphatro_cassette_interface =
{
cassette_default_formats,
NULL,
(cassette_state) (CASSETTE_PLAY | CASSETTE_MOTOR_DISABLED | CASSETTE_SPEAKER_ENABLED),
(cassette_state) (CASSETTE_PLAY | CASSETTE_MOTOR_ENABLED | CASSETTE_SPEAKER_ENABLED),
"alphatro_cass",
NULL
};
@ -489,7 +491,7 @@ static MACHINE_CONFIG_START( alphatro, alphatro_state )
MCFG_DEVICE_ADD("usart", I8251, 0)
MCFG_I8251_TXD_HANDLER(WRITELINE(alphatro_state, txdata_callback))
MCFG_DEVICE_ADD("usart_clock", CLOCK, 19225) // USART clock - this value loads a real tape
MCFG_DEVICE_ADD("usart_clock", CLOCK, 19225)
MCFG_CLOCK_SIGNAL_HANDLER(WRITELINE(alphatro_state, write_usart_clock))
MCFG_CASSETTE_ADD("cassette", alphatro_cassette_interface)
@ -511,7 +513,7 @@ MACHINE_CONFIG_END
***************************************************************************/
ROM_START( alphatro )
ROM_REGION( 0x10000, "maincpu", ROMREGION_ERASE00)
ROM_REGION( 0x10000, "roms", ROMREGION_ERASE00)
ROM_LOAD( "613256.ic-1058", 0x0000, 0x6000, CRC(ceea4cb3) SHA1(b332dea0a2d3bb2978b8422eb0723960388bb467) )
ROM_LOAD( "2764.ic-1038", 0xe000, 0x2000, CRC(e337db3b) SHA1(6010bade6a21975636383179903b58a4ca415e49) )