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Diffstat (limited to 'src/mame/machine/m6502_swap_op_d2_d7.h')
-rw-r--r--src/mame/machine/m6502_swap_op_d2_d7.h53
1 files changed, 53 insertions, 0 deletions
diff --git a/src/mame/machine/m6502_swap_op_d2_d7.h b/src/mame/machine/m6502_swap_op_d2_d7.h
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index 00000000000..7521ae8fff7
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+++ b/src/mame/machine/m6502_swap_op_d2_d7.h
@@ -0,0 +1,53 @@
+// license:BSD-3-Clause
+// copyright-holders:David Shah, David Haywood
+/***************************************************************************
+
+ m6502_swap_op_d2_d7.h
+
+ 6502 with instruction scrambling
+
+***************************************************************************/
+
+#ifndef MAME_M6502_SWAP_OP_D2_D7_H
+#define MAME_M6502_SWAP_OP_D2_D7_H
+
+#pragma once
+
+#include "cpu/m6502/m6502.h"
+#include "cpu/m6502/m6502d.h"
+
+class m6502_swap_op_d2_d7 : public m6502_device {
+public:
+ m6502_swap_op_d2_d7(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+protected:
+ class mi_decrypt : public mi_default {
+ public:
+
+ bool m_scramble_en = false;
+ bool m_next_scramble = false;
+
+ virtual ~mi_decrypt() {}
+ virtual uint8_t read_sync(uint16_t adr) override;
+
+ uint8_t descramble(uint8_t op);
+ };
+
+ class disassembler : public m6502_disassembler {
+ public:
+ mi_decrypt *mintf;
+
+ disassembler(mi_decrypt *m);
+ virtual ~disassembler() = default;
+ virtual u32 interface_flags() const override;
+ virtual u8 decrypt8(u8 value, offs_t pc, bool opcode) const override;
+ };
+
+ virtual void device_reset() override;
+ virtual void device_start() override;
+ virtual std::unique_ptr<util::disasm_interface> create_disassembler() override;
+};
+
+DECLARE_DEVICE_TYPE(M6502_SWAP_OP_D2_D7, m6502_swap_op_d2_d7)
+
+#endif // MAME_M6502_SWAP_OP_D2_D7_H