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-rw-r--r--src/mame/machine/konami1.cpp50
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;
+ }
+}