Catalogue of Arcade Emulation Software - the Absolute Reference

Valid XHTML 1.0! Valid CSS!



Large CAESAR Logo

Bubble Bobble

0.94u3 [Tormod Tjaberg]

0.27 [Chris Moore, Oliver White]


- The sequel to Bubble Bobble is Rainbow Island.

- Fujix has finished the game Bubble Bobble and he have a doubt about the end message text. This text scrolls up and when the textreaches the scores it becomes really hard to read it. I was wondering if this is who thecoin-op works. Should the scores disappear before the end text scrolls? Or should thescrolling text disappear before reaching the scores? This is not a bug. Fujix

- Clone boblbobl: When you take the clock, the time doesn't freeze. This is not a bug. I used to own the original pcb of Bobble Bobble (Bootleg) and the clock never freezed the enemy. All it did was change the stage colors to the clock freeze. So this version is accurate. comboace


- 0.111u5: David Haywood added clone Bubble Bobble (bootleg with 68705).

- 0.107u3: Trinity and Nicola Salmoria added support for real Bubble Bobble MCU. Added M6801 (1MHz) CPU4 and TAITO JPH1011P MCU rom (a78-01.17).

- 5th August 2006: Nicola Salmoria - As you'd probably noticed, the pics in the previous post are of the Bubble Bobble custom MCU. Despite being one of the most popular games of all times, and having been in MAME for many years, the emulation of this game has never been perfect due to the lack of the original ROM for the MCU. For some time, we had been using a 68705 program found in a bootleg board, believing it had been extracted from the original. However, monster behaviour was wrong and there were other problems, like the wrong behaviour of the clock item. After some study of the program and of the game schematics, it became clear that the original MCU is not a 68705 at all (the pinout doesn't match) but looked more like a 68701. The 68705 program had been written from scratch by the bootleggers using black box reverse engineering techniques, by running the original MCU and logging all its reads and writes from memory. Indeed, the 68705 program does a lot of reads from memory without doing anything with them--simply because the original MCU would read that memory and do some unknown action with it. Eventually, the useless 68705 program was replaced by simulation code inside the emulator, which greatly improved the emulation accuracy. Monster behaviour was improved, the clock item behaviour fixed. However, there were still some unknown things, like how the randomisation of the EXTEND bubbles really worked. At last, thanks to excellent work by Trinity, the original MCU ROM has been extracted. This required removing the cover from the chip, taking photographs of it under a microscope, and manually decoding the contents of the ROM bit by bit. The photo shown in the previous post confirms that it's in the 6801 class, not a 68701 however as it was conjectured, but a 6801U4. With this ROM, we finally have the final piece of the puzzle for a 100% guaranteed perfect emulation. Checking the original MCU program was very interesting. It was designed to provide many protection features that were eventually not used by the game, like: * Process coin inputs and update the credit counter * Handle the number of remaining lives for both players * Handle the current round number * Handle variable speed incrementing for four variables and * Return values from a 1280 bytes table of seemingly random data. The reasons why those features were not used are probably various. Some of them were probably awkward to use because they require to one one frame for the MCU to process the data, others weren't flexible enough like the coin input processing that wouldn't allow for coinage settings different from the ones hardcoded in the MCU (though versions of Bubble Bobble with different coinage settings don't seem to have been made anyway).
So, how close was the simulation to the real thing? Very close; "too good", actually. Let's see why. The clock item behaviour was spot on, but off by one frame (the simulation made the counter expire one frame too late). The EXTEND randomisation simply doesn't exist in the original MCU. While the simulation code used a RNG to provide truly random letters, the original MCU simply increases the counter every frame. This seriously affects the game, making the EXTEND letters predictable. Since a new bubble enters the screen exactly 128 frames after the previous one, and the remainder of 128 / 6 is 2, this means that if you get consecutive letters each one will be 2 places after the previous one. So if you get 3 letters you can get either E, T, N or X, E, D. After that they will repeat. There are exceptions, though: if you create a new bubble in exactly the same frame when a new bubble should enter the screen, the bubble is delayed by one frame. So by timing the fire button exactly right you can change the bubble order. In theory you could get all 6 letters in a single level--let me know if you manage to do that! Also, new bubbles will not appear if there are already 16 bubbles on the screen, so that will change the order as well. The last, and most important, thing that the MCU does is compare the player coordinates with the monsters. The results are returned as flags indicating whether each coordinate is >, =, or <, and the absolute difference. This was done correctly in the simulation code, however there appears to be a bug in the original MCU. The code there attempts to check if the player collided with a moster and set a flag and indicate which monster in that case, but it just doesn't work. It would set the flag even if the player's Y coordinate matches one monster and the X coordinate matches a different monster! This isn't much of a problem since the main program just ignores the flag--the collision detection is done correctly by the second Z80. However, the MCU also completely stops processing the monster coordinates as soon as it finds a monster whose X coordinate is within 8 pixels of the player. So e.g. if you have a monster right above you three platforms up, and that monster is the first in the list, the other monsters could stop following you. This is a very subtle effect that's completely unnoticeable from what I can tell, though in theory it exists.

- 0.106u12: MASH added plds ($0, 200, 400 - pal16r4.u36, pal16l8.u38 and pal16l8.u4) to clone Bobble Bobble.

- 6th June 2006: Guru - Bobble Bobble (Taito 1986) bootleg arrived from Korea today. Thanks to GP-Lee.

- 24th February 2006: Nicola Salmoria - The emulation of Bubble Bobble is already virtually perfect, but there is still a doubt about the clock item. Currently, when you pick it up the enemies stop but the bubbles continue moving. It would make sense if the bubbles stopped moving too, and this idea is corroborated by the way variables are set up in the MCU shared RAM. The MCU would be responsible for stopping the bubbles and make them start again when the clock effect ends. What we need is to verify the behaviour on an original board. Bootlegs don't count (the clock behaviour is definitely wrong in them), nor do other emulator or ports count. Only the original board matters. Can anyone help?

- 0.101u3: Fixed cpu1 rom ($0) length to 32kb.

- 0.94u3: Tormod Tjaberg added Bubble Bobble (newer set). Renamed (bublbobl) to (bublbob1).

- 0.93u1: Nicola Salmoria corrected input in Bubble Bobble (dipswitches etc.). Added 'ROM Type', changed 'Language' to 'Mode' and removed 'Service Mode' dipswitch.

- 0.90: Nicola Salmoria updated the Bubble Bobble driver. Removed 68705 CPU emulation, since that's not what the original used, simulated the 68701 MCU (enemy movement should now be correct), fixed clock item behaviour (now enemies start moving again after 10 seconds), supported coin lockout and emulated the boblbobl protection device (getting rid of the ROM patches).

- 0.88u7: Changed VSync to 59Hz.

- 0.78u4: Quench improved sound in clone Miss Bubble 2 (removed YM2203 sound and set the baddump flag for the sound1 rom).

- 0.78u3: David Haywood fixed clone boblbobl from crashing in 0.78u2.

- 0.77u3: Angelo Salese hooked up Backgrounds in Miss Bubble 2.

- 2nd December 2003: Angelo Salese emulated the background graphics in Miss Bubble 2.

- 30th November 2003: David Haywood decoded the background graphics in Miss Bubble 2, but they're not emulated yet.

- 0.60: Added clone Miss Bubble 2.

- 25th April 2002: Nicola Salmoria fixed the sprite colors in Miss Bubble 2, however the background graphics are not yet emulated.

- 24th April 2002: David Haywood also sent in a driver for Miss Bubble 2, a bootleg of the original Bubble Bobble with redesigned levels and redrawn graphics, however the driver lacks correct colors and sound.

- 0.37b4: Changed Z80 CPU4 clock speed to 3MHz and added prom (video timing). Changed cpu1 rom address to $10000 and fixed rom names.

- 0.36RC1: Added clone Bubble Bobble (US set 2).

- 0.35b11: Brad Oliver added clone Bubble Bobble (US).

- 17th April 1999: Brad Oliver added another Bubble Bobble romset.

- 0.35b6: Replaced M6805 CPU4 with M68705.

- 0.35b5: Changed M6805 CPU4 clock speed to 2MHz.

- 0.35b3: Nicola Salmoria support for the ORIGINAL version of Bubble Bobble, with 68705 code from a pirate board. Wizards *do* throw stones in this version. Also fixed big sprites in Tokio, and unified it with Bubble Bobble. Added M6805 (1.5 MHz) CPU4. The original version is the only one where wizards throw stones. The protection feature which randomizes the EXTEND letters in the original version is not emulated properly. Nicola fixed also big sprites in Tokio and unified it with Bubble Bobble.

- 0.34RC2: Fixed YM2203/YM3526 clock speeds to 3MHz.

- 0.34b8: Changed YM-3812 sound to YM-3526.

- 0.34b2: Tatsuyuki Satoh fixed music in Bubble Bobble to stay in sync now.

- 0.33b6: Changed description of Bobble Bobble (bootleg Bubble Bobble, alternate version) to 'Super Bobble Bobble'.

- 0.31: Nicola Salmoria added music in Bubble Bobble (Sound Blaster needed).

- 0.30: Nicola Salmoria added partial emulated sound in Bubble Bobble (only the YM2203 chip, therefore only some sound effects - no music).

- 0.29: Brad Oliver added clone Bobble Bobble (bootleg Bubble Bobble, alternate version). Bubble Bobble doesn't work in this release. Use Bobble Bobble or Super Bobble Bobble instead, they work much better than Bubble Bobble ever did.

- 0.28: Aaron Giles added a new function to dynamically modify the palette. Many games use this feature like Bubble Bobble.

- 0.27: Chris Moore added Bubble Bobble (Taito 1986) and Bobble Bobble (bootleg). The original version doesn't seem to behave correctly, probably due to the copy protection. Use the bootleg instead. The colors are accurate, but the color space is downgraded from 4x4x4 to 3x3x2. Sound effect codes from Oliver White. Drivers are now allowed to modify the RAM and ROM pointers to implement bank switching. Bubble Bobble uses this.


- Trap enemies inside bubbles.

- Burst bubbles with your horns or fins.

- Higher points are scored when bursting several bubbles at the same time.

- You can jump over bubbles.

- One stage cleared when all enemies are destroyed.

LEVELS: 100 (+ 3 secret rooms)

Other Emulators:

* CottAGE

* JEmu2

* Raine

Category: Platform 2

Recommended Games:

Bubble Bobble 2

Bubble Memories - The Story Of Bubble Bob

Ultra Balloon


Joust 2 - Survival of the Fittest

Chack'n Pop

Mario Bros.

Mario Bros. (PlayChoice-10)

Bomb Jack

Vs. Mighty Bomb Jack

Bombjack Twin

The FairyLand Story

TeddyBoy Blues

Rainbow Islands

Dark Tower

Don Doko Don


Snow Bros. - Nick & Tom

Snow Bros. 2 / Otenki Paradise

Snow Brothers 3 - Magical Adventure

Tumble Pop

Berlin Wall

Diet Go Go

Funky Jet

Saboten Bombers

Jump Kids

Metal Saver

Pang Pang

Fancy World - Earth of Crisis

Toppy & Rappy

Bomb Kick

Head Panic

Penguin Brothers

Romset: 549 kb / 18 files / 172 zip