// license:BSD-3-Clause // copyright-holders:Nigel Barnes /********************************************************************** Ramamp Computers Sideways RAM/ROM Board http://chrisacorns.computinghistory.org.uk/8bit_Upgrades/RAMAMP_SidewaysRAMROM.html **********************************************************************/ #include "emu.h" #include "ramamp.h" //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** DEFINE_DEVICE_TYPE(BBC_RAMAMP, bbc_ramamp_device, "bbc_ramamp", "Ramamp Sideways RAM/ROM Board"); //------------------------------------------------- // INPUT_PORTS( ramamp ) //------------------------------------------------- static INPUT_PORTS_START(ramamp) PORT_START("wp") PORT_CONFNAME(0x01, 0x00, "Write Protect Sideways RAM") PORT_CONFSETTING(0x00, DEF_STR(No)) PORT_CONFSETTING(0x01, DEF_STR(Yes)) INPUT_PORTS_END //------------------------------------------------- // input_ports - device-specific input ports //------------------------------------------------- ioport_constructor bbc_ramamp_device::device_input_ports() const { return INPUT_PORTS_NAME(ramamp); } //------------------------------------------------- // device_add_mconfig - add device configuration //------------------------------------------------- void bbc_ramamp_device::device_add_mconfig(machine_config &config) { /* 6 rom sockets, 32K dynamic ram */ BBC_ROMSLOT16(config, m_rom[8], bbc_rom_devices, nullptr); BBC_ROMSLOT16(config, m_rom[9], bbc_rom_devices, nullptr); BBC_ROMSLOT16(config, m_rom[10], bbc_rom_devices, "ram").set_fixed_ram(true); BBC_ROMSLOT16(config, m_rom[11], bbc_rom_devices, nullptr); BBC_ROMSLOT16(config, m_rom[12], bbc_rom_devices, nullptr); BBC_ROMSLOT16(config, m_rom[13], bbc_rom_devices, "ram").set_fixed_ram(true); BBC_ROMSLOT16(config, m_rom[14], bbc_rom_devices, nullptr); BBC_ROMSLOT16(config, m_rom[15], bbc_rom_devices, nullptr); } //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // bbc_ramamp_device - constructor //------------------------------------------------- bbc_ramamp_device::bbc_ramamp_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock) : device_t(mconfig, BBC_RAMAMP, tag, owner, clock) , device_bbc_internal_interface(mconfig, *this) , m_rom(*this, "romslot%u", 0U) , m_wp(*this, "wp") { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void bbc_ramamp_device::device_start() { /* move internal roms to board */ memmove(m_region_swr->base() + 0x2c000, m_region_swr->base(), 0x8000); memmove(m_region_swr->base() + 0x38000, m_region_swr->base() + 0x8000, 0x8000); memset(m_region_swr->base(), 0xff, 0x10000); /* register for save states */ save_item(NAME(m_romsel)); } //************************************************************************** // IMPLEMENTATION //************************************************************************** uint8_t bbc_ramamp_device::paged_r(offs_t offset) { uint8_t data = 0xff; switch (m_romsel) { case 0: case 1: case 2: case 3: /* motherboard rom sockets */ if (m_mb_rom[m_romsel] && m_mb_rom[m_romsel]->present()) { data = m_mb_rom[m_romsel]->read(offset); } else { data = m_region_swr->base()[offset + (m_romsel << 14)]; } break; default: /* expansion board sockets */ if (m_rom[m_romsel] && m_rom[m_romsel]->present()) { data = m_rom[m_romsel]->read(offset); } else { data = m_region_swr->base()[offset + (m_romsel << 14)]; } break; } return data; } void bbc_ramamp_device::paged_w(offs_t offset, uint8_t data) { switch (m_romsel) { case 0: case 1: case 2: case 3: /* motherboard rom sockets */ if (m_mb_rom[m_romsel]) { m_mb_rom[m_romsel]->write(offset, data); } break; case 10: case 13: /* expansion board sockets */ if (m_rom[m_romsel] && !m_wp->read()) { m_rom[m_romsel]->write(offset, data); } break; default: /* expansion board sockets */ if (m_rom[m_romsel]) { m_rom[m_romsel]->write(offset, data); } break; } }