// license:BSD-3-Clause // copyright-holders:Curt Coder /********************************************************************** COMX-35 80-Column Card emulation **********************************************************************/ /* (c) 1985 Comx World Operations PCB Layout ---------- F-003-CLM-REV 1 |---------------| | CN1 | |---| |---------------------------| | | | MC14174 LS86 LS175 LS10 LS161 | | 14.31818MHz | | LS245 LS04 | | ROM1 6845 CN2 | | LS374 LS165 | |LD2 LS138 LS157 LS157 | |LD1 6116 ROM2 SW1 | | LS126 LS32 LS157 | |-----------------------------------------------| Notes: All IC's shown. 6845 - Motorola MC6845P CRT Controller 6116 - Motorola MCM6116P15 2Kx8 Asynchronous CMOS Static RAM ROM1 - Mitsubishi 2Kx8 EPROM "C" ROM2 - Mitsubishi 2Kx8 EPROM "P" CN1 - COMX-35 bus PCB edge connector CN2 - RCA video output connector LD1 - LED LD2 - LED SW1 - switch */ #include "emu.h" #include "clm.h" #include "screen.h" //************************************************************************** // MACROS/CONSTANTS //************************************************************************** #define MC6845_TAG "mc6845" #define MC6845_SCREEN_TAG "screen80" #define VIDEORAM_SIZE 0x800 //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** DEFINE_DEVICE_TYPE(COMX_CLM, comx_clm_device, "comx_clm", "COMX 80 Column Card") //------------------------------------------------- // ROM( comx_clm ) //------------------------------------------------- ROM_START( comx_clm ) ROM_REGION( 0x2000, "c000", 0 ) ROM_DEFAULT_BIOS( "v11" ) ROM_SYSTEM_BIOS( 0, "v10", "v1.0" ) ROMX_LOAD( "p 1.0.cl1", 0x0000, 0x0800, CRC(b417d30a) SHA1(d428b0467945ecb9aec884211d0f4b1d8d56d738), ROM_BIOS(1) ) ROM_SYSTEM_BIOS( 1, "v11", "v1.1" ) ROMX_LOAD( "p 1.1.cl1", 0x0000, 0x0800, CRC(0a2eaf19) SHA1(3f1f640caef964fb47aaa147cab6d215c2b30e9d), ROM_BIOS(2) ) ROM_REGION( 0x800, MC6845_TAG, 0 ) ROMX_LOAD( "c 1.0.cl4", 0x0000, 0x0800, CRC(69dd7b07) SHA1(71d368adbb299103d165eab8359a97769e463e26), ROM_BIOS(1) ) ROMX_LOAD( "c 1.1.cl4", 0x0000, 0x0800, CRC(dc9b5046) SHA1(4e041cec03dda6dba5e2598d060c49908a4fab2a), ROM_BIOS(2) ) ROM_END //------------------------------------------------- // rom_region - device-specific ROM region //------------------------------------------------- const tiny_rom_entry *comx_clm_device::device_rom_region() const { return ROM_NAME( comx_clm ); } //------------------------------------------------- // mc6845 //------------------------------------------------- MC6845_UPDATE_ROW( comx_clm_device::crtc_update_row ) { for (int column = 0; column < x_count; column++) { uint8_t code = m_video_ram[((ma + column) & 0x7ff)]; uint16_t addr = (code << 3) | (ra & 0x07); uint8_t data = m_char_rom->base()[addr & 0x7ff]; if (BIT(ra, 3) && column == cursor_x) { data = 0xff; } for (int bit = 0; bit < 8; bit++) { int x = (column * 8) + bit; bitmap.pix32(vbp + y, hbp + x) = m_palette->pen(BIT(data, 7) && de); data <<= 1; } } } //------------------------------------------------- // GFXDECODE( comx_clm ) //------------------------------------------------- static GFXDECODE_START( comx_clm ) GFXDECODE_ENTRY(MC6845_TAG, 0x0000, gfx_8x8x1, 0, 1) GFXDECODE_END //------------------------------------------------- // device_add_mconfig - add device configuration //------------------------------------------------- MACHINE_CONFIG_MEMBER( comx_clm_device::device_add_mconfig ) MCFG_SCREEN_ADD_MONOCHROME(MC6845_SCREEN_TAG, RASTER, rgb_t::white()) MCFG_SCREEN_UPDATE_DEVICE(MC6845_TAG, mc6845_device, screen_update) MCFG_SCREEN_SIZE(80*8, 24*8) MCFG_SCREEN_VISIBLE_AREA(0, 80*8-1, 0, 24*8-1) MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) MCFG_SCREEN_REFRESH_RATE(50) MCFG_GFXDECODE_ADD("gfxdecode", "palette", comx_clm) MCFG_PALETTE_ADD_MONOCHROME("palette") MCFG_MC6845_ADD(MC6845_TAG, MC6845, MC6845_SCREEN_TAG, XTAL_14_31818MHz/7) MCFG_MC6845_SHOW_BORDER_AREA(true) MCFG_MC6845_CHAR_WIDTH(8) MCFG_MC6845_UPDATE_ROW_CB(comx_clm_device, crtc_update_row) MACHINE_CONFIG_END //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // comx_clm_device - constructor //------------------------------------------------- comx_clm_device::comx_clm_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, COMX_CLM, tag, owner, clock), device_comx_expansion_card_interface(mconfig, *this), device_gfx_interface(mconfig, *this, nullptr, "palette"), m_crtc(*this, MC6845_TAG), m_palette(*this, "palette"), m_rom(*this, "c000"), m_char_rom(*this, MC6845_TAG), m_video_ram(*this, "video_ram") { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void comx_clm_device::device_start() { // allocate memory m_video_ram.allocate(VIDEORAM_SIZE); // state saving save_item(NAME(m_ds)); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void comx_clm_device::device_reset() { } //------------------------------------------------- // comx_ef4_r - external flag 4 read //------------------------------------------------- int comx_clm_device::comx_ef4_r() { return m_ds ? m_crtc->hsync_r() : CLEAR_LINE; } //------------------------------------------------- // comx_mrd_r - memory read //------------------------------------------------- uint8_t comx_clm_device::comx_mrd_r(address_space &space, offs_t offset, int *extrom) { uint8_t data = 0xff; if (offset >= 0xc000 && offset < 0xc800) { data = m_rom->base()[offset & 0x7ff]; } else if (offset >= 0xd000 && offset < 0xd800) { data = m_video_ram[offset & 0x7ff]; } else if (offset == 0xd801) { data = m_crtc->register_r(space, 0); } return data; } //------------------------------------------------- // comx_mwr_w - memory write //------------------------------------------------- void comx_clm_device::comx_mwr_w(address_space &space, offs_t offset, uint8_t data) { if (offset >= 0xd000 && offset < 0xd800) { m_video_ram[offset & 0x7ff] = data; } else if (offset == 0xd800) { m_crtc->address_w(space, 0, data); } else if (offset == 0xd801) { m_crtc->register_w(space, 0, data); } }