diff options
Diffstat (limited to 'src/mame/machine/konami1.cpp')
-rw-r--r-- | src/mame/machine/konami1.cpp | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/src/mame/machine/konami1.cpp b/src/mame/machine/konami1.cpp new file mode 100644 index 00000000000..c0240bcbc78 --- /dev/null +++ b/src/mame/machine/konami1.cpp @@ -0,0 +1,50 @@ +// license:BSD-3-Clause +// copyright-holders:Olivier Galibert +/*************************************************************************** + + The Konami_1 CPU is a 6809 with opcodes scrambled. + +***************************************************************************/ + +#include "emu.h" +#include "konami1.h" + +const device_type KONAMI1 = &device_creator<konami1_device>; + +konami1_device::konami1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) + : m6809_base_device(mconfig, "KONAMI-1", tag, owner, clock, KONAMI1, 1, "konami1", __FILE__) +{ + m_boundary = 0x0000; +} + +void konami1_device::device_start() +{ + m_mintf = new mi_konami1(m_boundary); + m6809_base_device::device_start(); +} + +void konami1_device::set_encryption_boundary(UINT16 adr) +{ + m_boundary = adr; + if(m_mintf) + static_cast<mi_konami1 *>(m_mintf)->m_boundary = adr; +} + +konami1_device::mi_konami1::mi_konami1(UINT16 adr) +{ + m_boundary = adr; +} + +UINT8 konami1_device::mi_konami1::read_opcode(UINT16 adr) +{ + UINT8 val = m_sdirect->read_byte(adr); + if(adr < m_boundary) + return val; + switch(adr & 0xa) { + default: + case 0x0: return val ^ 0x22; + case 0x2: return val ^ 0x82; + case 0x8: return val ^ 0x28; + case 0xa: return val ^ 0x88; + } +} |