// license:BSD-3-Clause // copyright-holders:Sandro Ronco /*************************************************************************** rom.c KC 85 ROM modules emulation Supported modules: - Generic 8KB ROM module - M006 BASIC - M033 TypeStar ***************************************************************************/ #include "emu.h" #include "rom.h" #define REGION_TAG "rom" /*************************************************************************** IMPLEMENTATION ***************************************************************************/ ROM_START( kc_rom ) ROM_REGION(0x4000, REGION_TAG, ROMREGION_ERASEFF) ROM_END //************************************************************************** // GLOBAL VARIABLES //************************************************************************** DEFINE_DEVICE_TYPE(KC_STANDARD, kc_8k_device, "kc_8k", "Standard 8K ROM module") DEFINE_DEVICE_TYPE(KC_M006, kc_m006_device, "kc_m006", "M006 BASIC") DEFINE_DEVICE_TYPE(KC_M033, kc_m033_device, "kc_m033", "M033 TypeStar") //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // kc_8k_device - constructor //------------------------------------------------- kc_8k_device::kc_8k_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock) : kc_8k_device(mconfig, KC_STANDARD, tag, owner, clock) { } kc_8k_device::kc_8k_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, const XTAL &clock) : device_t(mconfig, type, tag, owner, clock) , device_kcexp_interface(mconfig, *this) , m_slot(nullptr), m_mei(0), m_rom(nullptr), m_enabled(0), m_base(0) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void kc_8k_device::device_start() { m_slot = dynamic_cast(owner()); m_rom = memregion(REGION_TAG)->base(); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void kc_8k_device::device_reset() { m_enabled = 0; m_base = 0; m_mei = 0; } //------------------------------------------------- // rom_region - device-specific ROM region //------------------------------------------------- const tiny_rom_entry *kc_8k_device::device_rom_region() const { return ROM_NAME( kc_rom ); } /*------------------------------------------------- get_cart_base -------------------------------------------------*/ uint8_t* kc_8k_device::get_cart_base() { return m_rom; } /*------------------------------------------------- module control write -------------------------------------------------*/ void kc_8k_device::control_w(uint8_t data) { if (m_mei) { m_enabled = BIT(data, 0); m_base = (data & 0xe0) << 8; } } /*------------------------------------------------- read -------------------------------------------------*/ void kc_8k_device::read(offs_t offset, uint8_t &data) { if (offset >= m_base && offset < (m_base + 0x2000) && m_enabled && m_mei) { data = m_rom[offset - m_base]; // clear the MEO line for disable other modules with less priority m_slot->meo_w(CLEAR_LINE); } } /*------------------------------------------------- MEI line write -------------------------------------------------*/ WRITE_LINE_MEMBER( kc_8k_device::mei_w ) { m_mei = state; // update MEO line m_slot->meo_w(state); } //************************************************************************** // M006 BASIC //************************************************************************** //------------------------------------------------- // kc_m006_device - constructor //------------------------------------------------- kc_m006_device::kc_m006_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock) : kc_8k_device(mconfig, KC_M006, tag, owner, clock) { } /*------------------------------------------------- module control write -------------------------------------------------*/ void kc_m006_device::control_w(uint8_t data) { if (m_mei) { m_enabled = BIT(data, 0); m_base = (data & 0xc0) << 8; } } /*------------------------------------------------- read -------------------------------------------------*/ void kc_m006_device::read(offs_t offset, uint8_t &data) { if (offset >= m_base && offset < (m_base + 0x4000) && m_enabled) { data = m_rom[offset - m_base]; // clear the MEO line for disable other modules with less priority m_slot->meo_w(CLEAR_LINE); } } //************************************************************************** // M033 TypeStar module //************************************************************************** //------------------------------------------------- // kc_m033_device - constructor //------------------------------------------------- kc_m033_device::kc_m033_device(const machine_config &mconfig, const char *tag, device_t *owner, const XTAL &clock) : kc_8k_device(mconfig, KC_M033, tag, owner, clock) , m_bank(0) { } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void kc_m033_device::device_reset() { kc_8k_device::device_reset(); m_bank = 0; } /*------------------------------------------------- module control write -------------------------------------------------*/ void kc_m033_device::control_w(uint8_t data) { if (m_mei) { m_enabled = BIT(data, 0); m_base = (data & 0xc0) << 8; m_bank = BIT(data, 4); } } /*------------------------------------------------- read -------------------------------------------------*/ void kc_m033_device::read(offs_t offset, uint8_t &data) { if (offset >= m_base && offset < (m_base + 0x2000) && m_enabled && m_mei) { data = m_rom[(offset - m_base) | (m_bank<<13)]; // clear the MEO line for disable other modules with less priority m_slot->meo_w(CLEAR_LINE); } }