// license:BSD-3-Clause // copyright-holders:David Haywood /* apparently Deco CPU-6 used by ProGolf just seems to be a bitswap on the opcodes like 222, but not the same one not a complex scheme like CPU-7? */ #include "emu.h" #include "decocpu6.h" DEFINE_DEVICE_TYPE(DECO_CPU6, deco_cpu6_device, "decocpu6", "DECO CPU-6") deco_cpu6_device::deco_cpu6_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : m6502_device(mconfig, DECO_CPU6, tag, owner, clock) { } void deco_cpu6_device::device_start() { mintf = std::make_unique(); init(); } void deco_cpu6_device::device_reset() { m6502_device::device_reset(); } uint8_t deco_cpu6_device::mi_decrypt::read_sync(uint16_t adr) { if (adr&1) return bitswap<8>(cache->read_byte(adr),6,4,7,5,3,2,1,0); else return cache->read_byte(adr); } std::unique_ptr deco_cpu6_device::create_disassembler() { return std::make_unique(); } u32 deco_cpu6_device::disassembler::interface_flags() const { return SPLIT_DECRYPTION; } u8 deco_cpu6_device::disassembler::decrypt8(u8 value, offs_t pc, bool opcode) const { return opcode && (pc & 1) ? bitswap<8>(value,6,4,7,5,3,2,1,0) : value; }