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Diffstat (limited to 'src/mess/machine/electron.c')
-rw-r--r-- | src/mess/machine/electron.c | 417 |
1 files changed, 0 insertions, 417 deletions
diff --git a/src/mess/machine/electron.c b/src/mess/machine/electron.c deleted file mode 100644 index 8510fe7f454..00000000000 --- a/src/mess/machine/electron.c +++ /dev/null @@ -1,417 +0,0 @@ -// license:BSD-3-Clause -// copyright-holders:Wilbert Pol -/****************************************************************************** - Acorn Electron driver - - MESS Driver By: - - Wilbert Pol - -******************************************************************************/ - -#include "emu.h" -#include "includes/electron.h" -#include "sound/beep.h" -#include "imagedev/cassette.h" - -void electron_state::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) -{ - switch (id) - { - case TIMER_TAPE_HANDLER: - electron_tape_timer_handler(ptr, param); - break; - case TIMER_SETUP_BEEP: - setup_beep(ptr, param); - break; - case TIMER_SCANLINE_INTERRUPT: - electron_scanline_interrupt(ptr, param); - break; - default: - assert_always(FALSE, "Unknown id in electron_state::device_timer"); - } -} - - -void electron_state::electron_tape_start() -{ - if (m_ula.tape_running ) - { - return; - } - m_ula.tape_steps = 0; - m_ula.tape_value = 0x80808080; - m_ula.high_tone_set = 0; - m_ula.bit_count = 0; - m_ula.tape_running = 1; - m_tape_timer->adjust(attotime::zero, 0, attotime::from_hz(4800)); -} - -void electron_state::electron_tape_stop() -{ - m_ula.tape_running = 0; - m_tape_timer->reset(); -} - -#define TAPE_LOW 0x00; -#define TAPE_HIGH 0xFF; - -TIMER_CALLBACK_MEMBER(electron_state::electron_tape_timer_handler) -{ - if ( m_ula.cassette_motor_mode ) - { - double tap_val; - tap_val = m_cassette->input(); - if ( tap_val < -0.5 ) - { - m_ula.tape_value = ( m_ula.tape_value << 8 ) | TAPE_LOW; - m_ula.tape_steps++; - } - else if ( tap_val > 0.5 ) - { - m_ula.tape_value = ( m_ula.tape_value << 8 ) | TAPE_HIGH; - m_ula.tape_steps++; - } - else - { - m_ula.tape_steps = 0; - m_ula.bit_count = 0; - m_ula.high_tone_set = 0; - m_ula.tape_value = 0x80808080; - } - if ( m_ula.tape_steps > 2 && ( m_ula.tape_value == 0x0000FFFF || m_ula.tape_value == 0x00FF00FF ) ) - { - m_ula.tape_steps = 0; - switch( m_ula.bit_count ) - { - case 0: /* start bit */ - m_ula.start_bit = ( ( m_ula.tape_value == 0x0000FFFF ) ? 0 : 1 ); - //logerror( "++ Read start bit: %d\n", m_ula.start_bit ); - if ( m_ula.start_bit ) - { - if ( m_ula.high_tone_set ) - { - m_ula.bit_count--; - } - } - else - { - m_ula.high_tone_set = 0; - } - break; - case 1: case 2: case 3: case 4: - case 5: case 6: case 7: case 8: - //logerror( "++ Read regular bit: %d\n", m_ula.tape_value == 0x0000FFFF ? 0 : 1 ); - m_ula.tape_byte = ( m_ula.tape_byte >> 1 ) | ( m_ula.tape_value == 0x0000FFFF ? 0 : 0x80 ); - break; - case 9: /* stop bit */ - m_ula.stop_bit = ( ( m_ula.tape_value == 0x0000FFFF ) ? 0 : 1 ); - //logerror( "++ Read stop bit: %d\n", m_ula.stop_bit ); - if ( m_ula.start_bit && m_ula.stop_bit && m_ula.tape_byte == 0xFF && ! m_ula.high_tone_set ) - { - electron_interrupt_handler( INT_SET, INT_HIGH_TONE ); - m_ula.high_tone_set = 1; - } - else if ( ! m_ula.start_bit && m_ula.stop_bit ) - { - //logerror( "-- Byte read from tape: %02x\n", m_ula.tape_byte ); - electron_interrupt_handler( INT_SET, INT_RECEIVE_FULL ); - } - else - { - logerror( "Invalid start/stop bit combination detected: %d,%d\n", m_ula.start_bit, m_ula.stop_bit ); - } - break; - } - m_ula.bit_count = ( m_ula.bit_count + 1 ) % 10; - } - } -} - -READ8_MEMBER(electron_state::electron_read_keyboard) -{ - UINT8 data = 0; - - //logerror( "PC=%04x: keyboard read from paged rom area, address: %04x", activecpu_get_pc(), offset ); - for (int i = 0; i < 14; i++) - { - if (!(offset & 1)) - data |= m_keybd[i]->read() & 0x0f; - - offset = offset >> 1; - } - //logerror( ", data: %02x\n", data ); - return data; -} - -READ8_MEMBER(electron_state::electron_jim_r) -{ - return 0xff; -} - -WRITE8_MEMBER(electron_state::electron_jim_w) -{ -} - -READ8_MEMBER(electron_state::electron_1mhz_r) -{ - return 0xff; -} - -WRITE8_MEMBER(electron_state::electron_1mhz_w) -{ -} - -READ8_MEMBER(electron_state::electron_ula_r) -{ - UINT8 data = ((UINT8 *)memregion("user1")->base())[0x43E00 + offset]; - switch ( offset & 0x0f ) - { - case 0x00: /* Interrupt status */ - data = m_ula.interrupt_status; - m_ula.interrupt_status &= ~0x02; - break; - case 0x01: /* Unknown */ - break; - case 0x04: /* Casette data shift register */ - electron_interrupt_handler(INT_CLEAR, INT_RECEIVE_FULL ); - data = m_ula.tape_byte; - break; - } - logerror( "ULA: read offset %02x: %02x\n", offset, data ); - return data; -} - -static const int electron_palette_offset[4] = { 0, 4, 5, 1 }; -static const UINT16 electron_screen_base[8] = { 0x3000, 0x3000, 0x3000, 0x4000, 0x5800, 0x5800, 0x6000, 0x5800 }; - -WRITE8_MEMBER(electron_state::electron_ula_w) -{ - int i = electron_palette_offset[(( offset >> 1 ) & 0x03)]; - logerror( "ULA: write offset %02x <- %02x\n", offset & 0x0f, data ); - switch( offset & 0x0f ) - { - case 0x00: /* Interrupt control */ - m_ula.interrupt_control = data; - break; - case 0x01: /* Unknown */ - break; - case 0x02: /* Screen start address #1 */ - m_ula.screen_start = ( m_ula.screen_start & 0x7e00 ) | ( ( data & 0xe0 ) << 1 ); - logerror( "screen_start changed to %04x\n", m_ula.screen_start ); - break; - case 0x03: /* Screen start addres #2 */ - m_ula.screen_start = ( m_ula.screen_start & 0x1c0 ) | ( ( data & 0x3f ) << 9 ); - logerror( "screen_start changed to %04x\n", m_ula.screen_start ); - break; - case 0x04: /* Cassette data shift register */ - break; - case 0x05: /* Interrupt clear and paging */ - /* rom page requests are honoured when currently bank 0-7 or 12-15 is switched in, - * or when 8-11 is currently switched in only switching to bank 8-15 is allowed. - * - * Rompages 10 and 11 both select the Basic ROM. - * Rompages 8 and 9 both select the keyboard. - */ - if ( ( ( m_ula.rompage & 0x0C ) != 0x08 ) || ( data & 0x08 ) ) - { - m_ula.rompage = data & 0x0f; - if ( m_ula.rompage == 8 || m_ula.rompage == 9 ) - { - m_ula.rompage = 8; - space.install_read_handler( 0x8000, 0xbfff, read8_delegate(FUNC(electron_state::electron_read_keyboard),this)); - } - else - { - space.install_read_bank( 0x8000, 0xbfff, "bank2"); - } - membank("bank2")->set_entry(m_ula.rompage); - } - if ( data & 0x10 ) - { - electron_interrupt_handler( INT_CLEAR, INT_DISPLAY_END ); - } - if ( data & 0x20 ) - { - electron_interrupt_handler( INT_CLEAR, INT_RTC ); - } - if ( data & 0x40 ) - { - electron_interrupt_handler( INT_CLEAR, INT_HIGH_TONE ); - } - if ( data & 0x80 ) - { - } - break; - case 0x06: /* Counter divider */ - if ( m_ula.communication_mode == 0x01) - { - m_beeper->set_frequency( 1000000 / ( 16 * ( data + 1 ) ) ); - } - break; - case 0x07: /* Misc. */ - m_ula.communication_mode = ( data >> 1 ) & 0x03; - switch( m_ula.communication_mode ) - { - case 0x00: /* cassette input */ - m_beeper->set_state( 0 ); - electron_tape_start(); - break; - case 0x01: /* sound generation */ - m_beeper->set_state( 1 ); - electron_tape_stop(); - break; - case 0x02: /* cassette output */ - m_beeper->set_state( 0 ); - electron_tape_stop(); - break; - case 0x03: /* not used */ - m_beeper->set_state( 0 ); - electron_tape_stop(); - break; - } - m_ula.screen_mode = ( data >> 3 ) & 0x07; - m_ula.screen_base = electron_screen_base[ m_ula.screen_mode ]; - m_ula.screen_size = 0x8000 - m_ula.screen_base; - m_ula.vram = (UINT8 *)space.get_read_ptr(m_ula.screen_base ); - logerror( "ULA: screen mode set to %d\n", m_ula.screen_mode ); - m_ula.cassette_motor_mode = ( data >> 6 ) & 0x01; - m_cassette->change_state(m_ula.cassette_motor_mode ? CASSETTE_MOTOR_ENABLED : CASSETTE_MOTOR_DISABLED, CASSETTE_MOTOR_DISABLED ); - m_ula.capslock_mode = ( data >> 7 ) & 0x01; - break; - case 0x08: case 0x0A: case 0x0C: case 0x0E: - // video_update - m_ula.current_pal[i+10] = (m_ula.current_pal[i+10] & 0x01) | (((data & 0x80) >> 5) | ((data & 0x08) >> 1)); - m_ula.current_pal[i+8] = (m_ula.current_pal[i+8] & 0x01) | (((data & 0x40) >> 4) | ((data & 0x04) >> 1)); - m_ula.current_pal[i+2] = (m_ula.current_pal[i+2] & 0x03) | ((data & 0x20) >> 3); - m_ula.current_pal[i] = (m_ula.current_pal[i] & 0x03) | ((data & 0x10) >> 2); - break; - case 0x09: case 0x0B: case 0x0D: case 0x0F: - // video_update - m_ula.current_pal[i+10] = (m_ula.current_pal[i+10] & 0x06) | ((data & 0x08) >> 3); - m_ula.current_pal[i+8] = (m_ula.current_pal[i+8] & 0x06) | ((data & 0x04) >> 2); - m_ula.current_pal[i+2] = (m_ula.current_pal[i+2] & 0x04) | (((data & 0x20) >> 4) | ((data & 0x02) >> 1)); - m_ula.current_pal[i] = (m_ula.current_pal[i] & 0x04) | (((data & 0x10) >> 3) | ((data & 0x01))); - break; - } -} - -void electron_state::electron_interrupt_handler(int mode, int interrupt) -{ - if ( mode == INT_SET ) - { - m_ula.interrupt_status |= interrupt; - } - else - { - m_ula.interrupt_status &= ~interrupt; - } - if ( m_ula.interrupt_status & m_ula.interrupt_control & ~0x83 ) - { - m_ula.interrupt_status |= 0x01; - m_maincpu->set_input_line(0, ASSERT_LINE ); - } - else - { - m_ula.interrupt_status &= ~0x01; - m_maincpu->set_input_line(0, CLEAR_LINE ); - } -} - -/************************************** - Machine Initialisation functions -***************************************/ - -TIMER_CALLBACK_MEMBER(electron_state::setup_beep) -{ - m_beeper->set_state( 0 ); - m_beeper->set_frequency( 300 ); -} - -void electron_state::machine_reset() -{ - membank("bank2")->set_entry(0); - - m_ula.communication_mode = 0x04; - m_ula.screen_mode = 0; - m_ula.cassette_motor_mode = 0; - m_ula.capslock_mode = 0; - m_ula.screen_mode = 0; - m_ula.screen_start = 0x3000; - m_ula.screen_base = 0x3000; - m_ula.screen_size = 0x8000 - 0x3000; - m_ula.screen_addr = 0; - m_ula.tape_running = 0; - m_ula.vram = (UINT8 *)m_maincpu->space(AS_PROGRAM).get_read_ptr(m_ula.screen_base); -} - -void electron_state::machine_start() -{ - UINT8 *lo_rom, *up_rom; - std::string region_tag; - memory_region *cart_rom = memregion(region_tag.assign(m_cart->tag()).append(GENERIC_ROM_REGION_TAG).c_str()); - - if (cart_rom) - up_rom = cart_rom->base(); - else - up_rom = memregion("user1")->base() + 12 * 0x4000; - if (cart_rom && cart_rom->bytes() > 0x4000) - lo_rom = cart_rom->base() + 0x4000; - else - lo_rom = memregion("user1")->base(); - - membank("bank2")->configure_entries(0, 1, lo_rom, 0x4000); - membank("bank2")->configure_entries(1, 11, memregion("user1")->base() + 0x04000, 0x4000); - membank("bank2")->configure_entries(12, 1, up_rom, 0x4000); - membank("bank2")->configure_entries(13, 3, memregion("user1")->base() + 0x34000, 0x4000); - - m_ula.interrupt_status = 0x82; - m_ula.interrupt_control = 0x00; - timer_set(attotime::zero, TIMER_SETUP_BEEP); - m_tape_timer = timer_alloc(TIMER_TAPE_HANDLER); -} - -DEVICE_IMAGE_LOAD_MEMBER( electron_state, electron_cart ) -{ - if (image.software_entry() == NULL) - { - UINT32 filesize = image.length(); - - if (filesize != 16384) - { - image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size: Only size 16384 is supported"); - return IMAGE_INIT_FAIL; - } - - m_cart->rom_alloc(filesize, GENERIC_ROM8_WIDTH, ENDIANNESS_LITTLE); - image.fread(m_cart->get_rom_base(), filesize); - return IMAGE_INIT_PASS; - } - else - { - int upsize = image.get_software_region_length("uprom"); - int losize = image.get_software_region_length("lorom"); - - if (upsize != 16384 && upsize != 0) - { - image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size for uprom"); - return IMAGE_INIT_FAIL; - } - - if (losize != 16384 && losize != 0) - { - image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size for lorom"); - return IMAGE_INIT_FAIL; - } - - m_cart->rom_alloc(upsize + losize, GENERIC_ROM8_WIDTH, ENDIANNESS_LITTLE); - - if (upsize) - memcpy(m_cart->get_rom_base(), image.get_software_region("uprom"), upsize); - - if (losize) - memcpy(m_cart->get_rom_base() + upsize, image.get_software_region("lorom"), losize); - - return IMAGE_INIT_PASS; - } -} |