// license:BSD-3-Clause // copyright-holders:Curt Coder /********************************************************************** VizaStar 64 XL4 cartridge emulation **********************************************************************/ /* PCB Layout ---------- RB84 (C) MICROPORT |===========================| |=| | |=| | |=| | |=| | |=| ROM | |=| | |=| | |=| | |===========================| ROM - Hitachi HN462732G 4Kx8 EPROM "V" */ #include "emu.h" #include "vizastar.h" //************************************************************************** // MACROS/CONSTANTS //************************************************************************** #define UNSCRAMBLE_ADDRESS(_offset) \ bitswap<16>(_offset,15,14,13,12,5,0,7,10,11,9,8,6,4,3,2,1) #define UNSCRAMBLE_DATA(_data) \ bitswap<8>(_data,7,6,0,5,1,4,2,3) //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** DEFINE_DEVICE_TYPE(C64_VIZASTAR, c64_vizastar_cartridge_device, "c64_vizastar", "VizaStar 64 XL4") //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // c64_vizastar_cartridge_device - constructor //------------------------------------------------- c64_vizastar_cartridge_device::c64_vizastar_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, C64_VIZASTAR, tag, owner, clock), device_c64_expansion_card_interface(mconfig, *this) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void c64_vizastar_cartridge_device::device_start() { } //------------------------------------------------- // c64_cd_r - cartridge data read //------------------------------------------------- uint8_t c64_vizastar_cartridge_device::c64_cd_r(offs_t offset, uint8_t data, int sphi2, int ba, int roml, int romh, int io1, int io2) { if (!roml) { data = UNSCRAMBLE_DATA(m_roml[UNSCRAMBLE_ADDRESS(offset & 0xfff)]); } return data; }