// license:BSD-3-Clause // copyright-holders:Nigel Barnes /********************************************************************** JAFA Systems ROMPlus-144 **********************************************************************/ #include "emu.h" #include "romp144.h" //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** DEFINE_DEVICE_TYPE(ELECTRON_ROMP144, electron_romp144_device, "electron_romp144", "JAFA Systems ROMPlus-144") //------------------------------------------------- // device_add_mconfig - add device configuration //------------------------------------------------- void electron_romp144_device::device_add_mconfig(machine_config &config) { /* rom sockets */ GENERIC_SOCKET(config, m_romslot[0], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[0]->set_device_load(FUNC(electron_romp144_device::rom0), this); GENERIC_SOCKET(config, m_romslot[1], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[1]->set_device_load(FUNC(electron_romp144_device::rom1), this); GENERIC_SOCKET(config, m_romslot[2], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[2]->set_device_load(FUNC(electron_romp144_device::rom2), this); GENERIC_SOCKET(config, m_romslot[3], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[3]->set_device_load(FUNC(electron_romp144_device::rom3), this); GENERIC_SOCKET(config, m_romslot[4], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[4]->set_device_load(FUNC(electron_romp144_device::rom4), this); GENERIC_SOCKET(config, m_romslot[5], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[5]->set_device_load(FUNC(electron_romp144_device::rom5), this); GENERIC_SOCKET(config, m_romslot[6], generic_plain_slot, "electron_rom", "bin,rom"); m_romslot[6]->set_device_load(FUNC(electron_romp144_device::rom6), this); } //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // electron_romp144_device - constructor //------------------------------------------------- electron_romp144_device::electron_romp144_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, ELECTRON_ROMP144, tag, owner, clock) , device_electron_cart_interface(mconfig, *this) , m_romslot(*this, "rom%u", 7) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void electron_romp144_device::device_start() { m_rom_select = 0xff; m_rom_latch = 0xff; save_item(NAME(m_rom_select)); save_item(NAME(m_rom_latch)); } //------------------------------------------------- // read - cartridge data read //------------------------------------------------- uint8_t electron_romp144_device::read(offs_t offset, int infc, int infd, int romqa, int oe, int oe2) { uint8_t data = 0xff; if (oe) { if (romqa) { if ((m_rom_select & 0x07) == 0x00) data = m_ram[offset & 0x3fff]; else data = m_romslot[(m_rom_select & 0x07) - 1]->read_rom(offset & 0x3fff); } else { if ((m_rom_select & 0x0f) == 0x08) data = m_ram[(offset & 0x3fff) | 0x4000]; else data = m_rom[offset & 0x1fff]; /* roms selected with a read to latch */ if ((offset & 0x3f00) == 0x3f00) { m_rom_latch = offset & 0x0f; } } } return data; } //------------------------------------------------- // write - cartridge data write //------------------------------------------------- void electron_romp144_device::write(offs_t offset, uint8_t data, int infc, int infd, int romqa, int oe, int oe2) { if (oe) { if (romqa) { if ((m_rom_select & 0x07) == 0x00) m_ram[offset & 0x3fff] = data; } else { if ((m_rom_select & 0x0f) == 0x08) m_ram[(offset & 0x3fff) | 0x4000] = data; /* roms selected with a write to select */ if ((offset & 0x3f00) == 0x3f00) { /* does the write match the read (upper RAM cannot be de-selected to protect *RSUBSTITUTE) */ if (m_rom_latch == (offset & 0x0f) && m_rom_select != 0x08) { m_rom_select = m_rom_latch; } } } } } //************************************************************************** // IMPLEMENTATION //************************************************************************** image_init_result electron_romp144_device::load_rom(device_image_interface &image, generic_slot_device *slot) { uint32_t size = slot->common_get_size("rom"); // socket accepts 8K and 16K ROM only if (size != 0x2000 && size != 0x4000) { image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size: Only 8K/16K is supported"); return image_init_result::FAIL; } slot->rom_alloc(0x4000, GENERIC_ROM8_WIDTH, ENDIANNESS_LITTLE); slot->common_load_rom(slot->get_rom_base(), size, "rom"); // mirror 8K ROMs uint8_t *crt = slot->get_rom_base(); if (size <= 0x2000) memcpy(crt + 0x2000, crt, 0x2000); return image_init_result::PASS; }