From c83d7fe44ef63400ab729dac706e05bedb07b287 Mon Sep 17 00:00:00 2001
From: David Haywood <28625134+DavidHaywood@users.noreply.github.com>
Date: Fri, 8 May 2020 14:02:12 +0100
Subject: [PATCH] add init to convert twinbeeb bubble dump into something the
 driver can actually use (nw) (#6646)

* add init to convert twinbeeb bubble dump into something the driver can actually use (nw)

* note checksum of reencoded data created by our function (nw)
---
 src/mame/drivers/nemesis.cpp | 49 +++++++++++++++++++++++++++++++++---
 src/mame/includes/nemesis.h  |  1 +
 2 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/src/mame/drivers/nemesis.cpp b/src/mame/drivers/nemesis.cpp
index bb36b83e07a..9fa97266383 100644
--- a/src/mame/drivers/nemesis.cpp
+++ b/src/mame/drivers/nemesis.cpp
@@ -481,6 +481,7 @@ void nemesis_state::bubsys_map(address_map &map)
 	map(0x054000, 0x054fff).ram().w(FUNC(nemesis_state::nemesis_colorram1_word_w)).share("colorram1");
 	map(0x055000, 0x055fff).ram().w(FUNC(nemesis_state::nemesis_colorram2_word_w)).share("colorram2");
 	map(0x056000, 0x056fff).ram().share("spriteram");
+	map(0x057000, 0x057fff).ram();
 	map(0x05a000, 0x05afff).ram().w(FUNC(nemesis_state::nemesis_palette_word_w)).share("paletteram");
 	map(0x05c001, 0x05c001).w("soundlatch", FUNC(generic_latch_8_device::write));
 	map(0x05c402, 0x05c403).portr("DSW0");
@@ -3038,8 +3039,11 @@ ROM_START( twinbeeb )
 	ROM_REGION( 0x80000, "maincpu", ROMREGION_ERASE00 )
 	ROM_LOAD16_WORD( "boot.bin", 0x000, 0x1e0, CRC(ee6e93d7) SHA1(7302c08a726a760f59d6837be8fd10bbd1f79da0) )
 
-	ROM_REGION( 0x40300, "bubblememory", 0 )
-	ROM_LOAD16_WORD_SWAP( "twinbee.bin", 0x00000, 0x40300, CRC(4d396a0a) SHA1(ee922a1bd7062c0fcf358f5079cca6424aadc975) )
+	ROM_REGION( 0x806*0x90, "bubblememory", ROMREGION_ERASE00 )
+//	ROM_LOAD16_WORD_SWAP( "bubble_twinbeeb", 0x000, 0x48360, CRC(21599cf5) SHA1(7eb068e10134d5c66f7f90f6d6b265353b7bd8be) ) // re-encoded data
+	
+	ROM_REGION( 0x806*0x80, "bubblememory_temp", 0 )
+	ROM_LOAD( "twinbee.bin", 0x00000, 0x40300, CRC(4d396a0a) SHA1(ee922a1bd7062c0fcf358f5079cca6424aadc975) )
 
 	ROM_REGION( 0x1000, "mcu", ROMREGION_ERASE00 ) // Fujitsu MCU
 	ROM_LOAD( "mcu", 0x0000, 0x1000, NO_DUMP )
@@ -3078,9 +3082,48 @@ void nemesis_state::bubsys_init()
 	m_bubsys_control_ram[3]=0x240;
 }
 
+
+void nemesis_state::bubsys_twinbeeb_init()
+{
+	// the twinbee bubble data is in a stripped down, predecoded state already, why?
+	// this reencodes it to something the loading code can actually use
+
+	uint8_t *src = memregion("bubblememory_temp")->base();
+	uint8_t *dst = memregion("bubblememory")->base();
+
+	for (int i = 0; i < 0x806; i++)
+	{
+		uint16_t crc = 0;
+		
+		int sourcebase = i * 0x80;
+		int destbase = i * 0x90;
+
+		for (int j = 0; j < 0x80; j++)
+		{
+			uint8_t dat = src[sourcebase + j];
+			dst[destbase + j + 0] |= (dat >> 6) & 0x03;
+			dst[destbase + j + 1] |= (dat << 2) & 0xfc;
+
+			crc += dat;
+		}
+
+		for (int j = 0; j < 0x82; j += 2)
+		{
+			uint8_t temp1 = dst[destbase + j + 0];
+			dst[destbase + j + 0] = dst[destbase + j + 1];
+			dst[destbase + j + 1] = temp1;
+		}
+
+		dst[destbase+0x83] = i >> 8;
+		dst[destbase+0x82] = i & 0xff;
+	}
+
+	bubsys_init();
+}
+
 GAME( 1985, bubsys,   0,         bubsys,    bubsys, nemesis_state, bubsys_init, ROT0,   "Konami", "Bubble System BIOS", MACHINE_IS_BIOS_ROOT )
 GAME( 1985, gradiusb, bubsys,    bubsys,    bubsys, nemesis_state, bubsys_init, ROT0,   "Konami", "Gradius (Bubble System)", MACHINE_UNEMULATED_PROTECTION )
-GAME( 1985, twinbeeb, bubsys,    bubsys,    bubsys, nemesis_state, bubsys_init, ROT0,   "Konami", "TwinBee (Bubble System)", MACHINE_NOT_WORKING | MACHINE_UNEMULATED_PROTECTION ) // doesn't seem to like the MCU simulation
+GAME( 1985, twinbeeb, bubsys,    bubsys,    bubsys, nemesis_state, bubsys_twinbeeb_init, ROT90,   "Konami", "TwinBee (Bubble System)", MACHINE_UNEMULATED_PROTECTION )
 // Bubble System RF2
 // Bubble System Galactic Warriors
 // Bubble System Attack Rush
diff --git a/src/mame/includes/nemesis.h b/src/mame/includes/nemesis.h
index 7abce049384..cec7817ddbd 100644
--- a/src/mame/includes/nemesis.h
+++ b/src/mame/includes/nemesis.h
@@ -61,6 +61,7 @@ public:
 	void blkpnthr(machine_config &config);
 
 	void bubsys_init();
+	void bubsys_twinbeeb_init();
 
 private:
 	/* memory pointers */