// license:BSD-3-Clause // copyright-holders:Curt Coder, smf /* Z80 Video Pak (c) 1983 Data 20 Corporation */ #include "emu.h" #include "z80videopak.h" #include "screen.h" //************************************************************************** // MACROS/CONSTANTS //************************************************************************** #define RAM_SIZE 0x800 #define HD46505SP_TAG "mc6845" #define MC6845_SCREEN_TAG "screen80" //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** DEFINE_DEVICE_TYPE(C64_Z80VIDEOPAK, c64_z80videopak_device, "c64_z80videopak", "Data20 Z80 Video Pak") //------------------------------------------------- // ROM( c64_z80videopak ) //------------------------------------------------- ROM_START( c64_z80videopak ) ROM_REGION( 0x800, HD46505SP_TAG, 0 ) ROM_LOAD( "c68297 vid pak cg.u18", 0x000, 0x800, CRC(9edf5e58) SHA1(4b244e6d94a7653a2e52c351589f0b469119fb04) ) ROM_END //------------------------------------------------- // rom_region - device-specific ROM region //------------------------------------------------- const tiny_rom_entry *c64_z80videopak_device::device_rom_region() const { return ROM_NAME( c64_z80videopak ); } //------------------------------------------------- // mc6845 //------------------------------------------------- MC6845_UPDATE_ROW( c64_z80videopak_device::crtc_update_row ) { pen_t const *const pen = m_palette->pens(); for (int column = 0; column < x_count; column++) { uint8_t const code = m_ram[((ma + column) & 0x7ff)]; uint16_t const addr = (m_case << 10) | ((code & 0x7f) << 3) | (ra & 0x07); uint8_t data = m_char_rom->base()[addr & 0x7ff]; if (column == cursor_x) { data = 0xff; } for (int bit = 0; bit < 8; bit++) { int const x = (column * 8) + bit; int const color = BIT(data ^ code, 7) && de; bitmap.pix(vbp + y, hbp + x) = pen[color]; data <<= 1; } } } //------------------------------------------------- // GFXDECODE( c64_videopak ) //------------------------------------------------- static GFXDECODE_START( gfx_c64_z80videopak ) GFXDECODE_ENTRY(HD46505SP_TAG, 0x0000, gfx_8x8x1, 0, 1) GFXDECODE_END //------------------------------------------------- // device_add_mconfig - add device configuration //------------------------------------------------- void c64_z80videopak_device::device_add_mconfig(machine_config &config) { c64_cpm_cartridge_device::device_add_mconfig(config); screen_device &screen(SCREEN(config, MC6845_SCREEN_TAG, SCREEN_TYPE_RASTER, rgb_t::white())); screen.set_screen_update(HD46505SP_TAG, FUNC(hd6845s_device::screen_update)); screen.set_size(80*8, 24*8); screen.set_visarea(0, 80*8-1, 0, 24*8-1); screen.set_refresh_hz(50); GFXDECODE(config, "gfxdecode", m_palette, gfx_c64_z80videopak); PALETTE(config, m_palette, palette_device::MONOCHROME); HD6845S(config, m_crtc, XTAL(14'318'181) / 8); m_crtc->set_screen(MC6845_SCREEN_TAG); m_crtc->set_show_border_area(true); m_crtc->set_char_width(8); m_crtc->set_update_row_callback(FUNC(c64_z80videopak_device::crtc_update_row)); } //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // c64_z80videopak_device - constructor //------------------------------------------------- c64_z80videopak_device::c64_z80videopak_device(const machine_config& mconfig, const char* tag, device_t* owner, uint32_t clock) : c64_cpm_cartridge_device(mconfig, C64_Z80VIDEOPAK, tag, owner, clock), m_crtc(*this, HD46505SP_TAG), m_palette(*this, "palette"), m_char_rom(*this, HD46505SP_TAG), m_ram(*this, "ram", RAM_SIZE, ENDIANNESS_LITTLE) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void c64_z80videopak_device::device_start() { // state saving save_item(NAME(m_case)); c64_cpm_cartridge_device::device_start(); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void c64_z80videopak_device::device_reset() { m_case = 0; m_exrom = 0; c64_cpm_cartridge_device::device_reset(); } //------------------------------------------------- // c64_cd_r - cartridge data read //------------------------------------------------- uint8_t c64_z80videopak_device::c64_cd_r(offs_t offset, uint8_t data, int sphi2, int ba, int roml, int romh, int io1, int io2) { if (!roml) { if (BIT(offset, 11)) data = m_ram[offset & 0x7ff]; else data = m_roml[offset & 0x7ff]; } else if (!io2 && !BIT(offset, 1)) { if (BIT(offset, 0)) data = m_crtc->register_r(); } return data; } //------------------------------------------------- // c64_cd_w - cartridge data write //------------------------------------------------- void c64_z80videopak_device::c64_cd_w(offs_t offset, uint8_t data, int sphi2, int ba, int roml, int romh, int io1, int io2) { c64_cpm_cartridge_device::c64_cd_w(offset, data, sphi2, ba, roml, romh, io1, io2); if ((!m_exrom && offset >= 0x9800 && offset < 0xa000) || (m_exrom && offset >= 0xf800 && offset < 0x10000)) { m_ram[offset & 0x7ff] = data; } else if (!io2 && !BIT(offset, 1)) { if (!BIT(offset, 0)) m_crtc->address_w(data); else m_crtc->register_w(data); } else if (!io2) { m_case = BIT(data, 0); // BIT(data, 1); // unknown // BIT(data, 2); // unknown m_exrom = BIT(data, 4); } }