Taito F3 Converted Game Cart Conversion:
That is a mouthful but let me explain!
When I bought my Taito F3 ( in early 2019) it came bundled with a “Puzzle Bobble 4” cart.
The picture of the listing was not very good quality and at the time I believed it was a legitimate F3 Game.
However, when it arrived you could easily tell that the labels on it were fake:
I didn’t complain or care too much because the price I paid was exceptionally low and everything worked.
Looking underneath the F3 game we can see that the Taito sticker seal has been peeled off from over the screw in the center of the cart and it is marked as: M20J0116A which is the product ID for Puzzle Bobble 2:
Upon opening the F3 cartridge up we can see that where there should be Mask Rom’s on the top and bottom rows for Graphic and sound Data that we have EPROM’s with uncovered windows:
Upon turning over the PCB you can see all the flux residue that was not cleaned up and the poor soldering by whoever converted this F3 game originally:
Has I was not happy owning a bootleg/conversion, I eventually bought the original Puzzle Bobble 2-4:
So now I had a conversion I no longer required, I decided I would do something special with it and convert it into a game I could not realistically afford and really wanted to play on original hardware and do a good job of it.
For Taito F3 conversions you have to pay very special heed to what PAL you have at position IC21:
This will either be a D77-14 or a D77-15.
D77-14 is used for Program EPROM’s that are 27c2001 (0x40000).
D77-15 is used for Program EPROM’s that are 27c4001 (0x80000).
I have a D77-15 so I need to find a Taito F3 game that uses 27c4001 EPROM’s and of the games I could convert to I decided on Elevator Action Returns.
Now I needed to de-solder all the EPROM’s for graphic and sound data:
Unfortunately at this time I didn’t yet have a de-soldering gun and was resorting to using a manual pump and a cheap hot air station to help pry out the EPROM’s and of all the 336 via’s I accidentally damaged one:
Since I was going to put sockets in place I decided I would do the trace repair on the top of the circuit board with thin Kyna wire so it could easily be concealed under a socket:
Which was threaded through the via, to be soldered on the reverse of the PCB along with the Sockets legs:
With this problem resolved I then cleared the solder mask from IC4 where I needed to place a socket for a position which was not already populated and proceeded to solder in all the required sockets:
I then used my EPROM Eraser to erase all the old EPROM’s:
Using the information from the Mame Taito_F3.cpp I had figured out that to do this conversion I would need to programme the EPROM’s with the data from the contents of the MAME elvactr.zip as follows:
ELEVATOR ACTION RETURNS TAITO F3 CONVERSION:
IC04 - 27C160 (100ns) Mame ROM : e02-01.4
IC08 - 27C160 (100ns) Mame ROM : e02-02.8
IC12 - 27C160 (100ns) Mame ROM : e02-03.12
IC17 - 27C4001 (100ns) Mame ROM : e02-16.17
IC18 - 27C4001 (100ns) Mame ROM : e02-10.18
IC19 - 27C4001 (100ns) Mame ROM : e02-11.19
IC20 - 27C4001 (100ns) Mame ROM : e02-12.20
IC32 - 27C2001 (120ns) Mame ROM : e02-13.32
IC33 - 27C2001 (120ns) Mame ROM : e02-14.33
IC38 - 27C160 (100ns) Mame ROM : e02-04.38
IC39 - 27C160 (100ns) Mame ROM : e02-05.39
IC43 - 27C160 (100ns) Mame ROM : e02-06.43
IC45 - 27C160 (100ns) Mame ROM : e02-07.45
IC47 - 27C160 (100ns) Mame ROM : e02-08.47
All the now programmed EPROM’s were then inserted in their appropriate sockets and EPROM windows covered up with electrical tape:
I then tested the cart on my Taito F3 and it booted fine, however I was getting some very strange random flickering single pixels at various certain places in the game as circled in the image below:
This problem is often caused in conversions by EPROM’s whose speed is too slow. Taito F3 hardware requires that everything apart from the two AUDIO PRG EPROM’s at positions IC32 & IC33 need to be running at 100ns or faster.
Since the game was running fine and the audio had no issues I only needed to look at the six EPROM’s that held graphic data (IC4, IC8, IC12, IC43, IC45 & IC47).
I dug out a spare known good 100ns 27C160 EPROM which I used to programme, replace and test each of those IC positions until I found the culprit bad EPROM which was then thrown away and I now had a perfect working version of Elevator Action Returns!
I then removed the old labels from the cart:
And as best as I could reproduced new labels for it making sure to add a note that it is a conversion:
I went to a local print shop and got a few printed out and then added them to my F3 cart:
And now to enjoy my new game:
