temporary debug code for creating rearranged ROMs

Author: David Haywood

src/mame/epoch/cassvisn.cpp

@@ -15,6 +15,7 @@ the linked 'design note' contains a large amount of useful information
 #include "bus/generic/slot.h"
 #include "bus/generic/carts.h"
 #include "cpu/upd777/upd777.h"
+#include "cpu/upd777/upd777dasm.h"
 
 #include "softlist_dev.h"
 
@@ -38,6 +39,8 @@ class cassvisn_state : public driver_device
 private:
 	required_device<cpu_device> m_maincpu;
 	required_device<generic_slot_device> m_cart;
+
+	u16 m_table[0xfe0/2];
 };
 
 static INPUT_PORTS_START( cassvisn )
@@ -49,6 +52,41 @@ DEVICE_IMAGE_LOAD_MEMBER(cassvisn_state::cart_load)
 	m_cart->rom_alloc(size, GENERIC_ROM16_WIDTH, ENDIANNESS_LITTLE);
 	m_cart->common_load_rom(m_cart->get_rom_base(), size, "prg");
 	memcpy(memregion("maincpu")->base(), m_cart->get_rom_base(), size);
+
+	upd777_disassembler::populate_addr_table(m_table);
+
+	if (size == 0xfe0)
+	{
+		u8 *ROM = memregion("maincpu")->base();
+
+		u8 m_newrom[0x1000];
+		std::fill(std::begin(m_newrom), std::end(m_newrom), 0xff);
+
+		for (int realadd = 0; realadd < 0x800; realadd++)
+		{
+			int found = -1;
+			for (int checkaddr = 0; checkaddr < 0xfe0/2; checkaddr++)
+			{
+				if (m_table[checkaddr] == realadd)
+					found = checkaddr;
+			}
+
+			if (found != -1)
+			{
+				m_newrom[(realadd * 2) + 1] = ROM[(found * 2) + 0];
+				m_newrom[(realadd * 2) + 0] = ROM[(found * 2) + 1];
+			}
+		}
+
+		FILE *fp;
+		fp=fopen("rearranged_rom.bin", "w+b");
+		if (fp)
+		{
+			fwrite(m_newrom, 0x1000, 1, fp);
+			fclose(fp);
+		}
+	}
+
 	return std::make_pair(std::error_condition(), std::string());
 }