// license:BSD-3-Clause // copyright-holders:Sandro Ronco /*************************************************************************** rom.c Z88 ROM cartridges emulation ***************************************************************************/ #include "emu.h" #include "rom.h" namespace { //************************************************************************** // TYPE DEFINITIONS //************************************************************************** // ======================> z88_32k_rom_device class z88_32k_rom_device : public device_t, public device_nvram_interface, public device_z88cart_interface { public: // construction/destruction z88_32k_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock); protected: z88_32k_rom_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock); // device_t implementation virtual void device_start() override ATTR_COLD; // device_nvram_interface implementation virtual void nvram_default() override { } virtual bool nvram_read(util::read_stream &file) override { auto const [err, actual] = util::read(file, get_cart_base(), get_cart_size()); return !err && (actual == get_cart_size()); } virtual bool nvram_write(util::write_stream &file) override { auto const [err, actual] = util::write(file, get_cart_base(), get_cart_size()); return !err; } virtual bool nvram_can_write() const override { return m_modified; // Save only if the EPROM has been programmed } // z88cart_interface implementation virtual uint8_t read(offs_t offset) override; virtual void write(offs_t offset, uint8_t data) override; virtual void vpp_w(int state) override { m_vpp_state = state; } virtual uint8_t* get_cart_base() override; virtual uint32_t get_cart_size() override { return 0x8000; } protected: // internal state uint8_t * m_rom; int m_vpp_state; bool m_modified; }; // ======================> z88_128k_rom_device class z88_128k_rom_device : public z88_32k_rom_device { public: // construction/destruction z88_128k_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock); protected: // z88cart_interface implementation virtual uint32_t get_cart_size() override { return 0x20000; } }; // ======================> z88_256k_rom_device class z88_256k_rom_device : public z88_32k_rom_device { public: // construction/destruction z88_256k_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock); protected: // z88cart_interface implementation virtual uint32_t get_cart_size() override { return 0x40000; } }; /*************************************************************************** IMPLEMENTATION ***************************************************************************/ //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // z88_32k_rom_device - constructor //------------------------------------------------- z88_32k_rom_device::z88_32k_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : z88_32k_rom_device(mconfig, Z88_32K_ROM, tag, owner, clock) { } z88_32k_rom_device::z88_32k_rom_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, type, tag, owner, clock) , device_nvram_interface(mconfig, *this) , device_z88cart_interface(mconfig, *this) , m_rom(nullptr) , m_vpp_state(0) , m_modified(false) { } //------------------------------------------------- // z88_128k_rom_device - constructor //------------------------------------------------- z88_128k_rom_device::z88_128k_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : z88_32k_rom_device(mconfig, Z88_128K_ROM, tag, owner, clock) { } //------------------------------------------------- // z88_256k_rom_device - constructor //------------------------------------------------- z88_256k_rom_device::z88_256k_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : z88_32k_rom_device(mconfig, Z88_256K_ROM, tag, owner, clock) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void z88_32k_rom_device::device_start() { m_rom = machine().memory().region_alloc(tag(), get_cart_size(), 1, ENDIANNESS_LITTLE)->base(); std::fill_n(m_rom, get_cart_size(), 0xff); save_item(NAME(m_vpp_state)); save_item(NAME(m_modified)); } /*------------------------------------------------- get_cart_base -------------------------------------------------*/ uint8_t* z88_32k_rom_device::get_cart_base() { return m_rom; } /*------------------------------------------------- read -------------------------------------------------*/ uint8_t z88_32k_rom_device::read(offs_t offset) { return m_rom[offset & (get_cart_size() - 1)]; } /*------------------------------------------------- write -------------------------------------------------*/ void z88_32k_rom_device::write(offs_t offset, uint8_t data) { if (m_vpp_state) { const uint32_t offset_mask = get_cart_size() - 1; if (m_rom[offset & offset_mask] & ~data) m_modified = true; m_rom[offset & offset_mask] &= data; } } } // anonymous namespace //************************************************************************** // GLOBAL VARIABLES //************************************************************************** DEFINE_DEVICE_TYPE_PRIVATE(Z88_32K_ROM, device_z88cart_interface, z88_32k_rom_device, "z88_32k_rom", "Z88 32KB ROM") DEFINE_DEVICE_TYPE_PRIVATE(Z88_128K_ROM, device_z88cart_interface, z88_128k_rom_device, "z88_128k_rom", "Z88 128KB ROM") DEFINE_DEVICE_TYPE_PRIVATE(Z88_256K_ROM, device_z88cart_interface, z88_256k_rom_device, "z88_256k_rom", "Z88 256KB ROM")