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Please HELP with 2 in 1 8K DIY CART


pcrock

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Hi friends.

I have a 2 in 1 cartridge with two 8K games that works PERFECT. The games are HERO (by Mania) and KUNG FU MASTER (by Activision \ Irem).
The circuit uses two ICs 74ls00 and 74ls10 and the Chip is MBM27128-30.
I did the dump file to backup and I sent it here at the post.
I would love to create a new BIN file with BeamRider and Tapper. But when I created the new eprom with that games I want, the cart does not work.
I tryed to create eproms with anothers games like Tapper and Pengo or Galaxian and Centipede but still never works. 
I also tryed to create roms with four games to use in another 4 in 1 8K games I have but not works too!!!
There are some matter with bankswitch???
Is possible I make a 2in1 or 4in 1 roms with the games I want to run on my carts??
Thanks friend
 

WhatsApp Image 2020-09-04 at 23.16.39 (3).jpeg

WhatsApp Image 2020-09-04 at 23.16.39 (2).jpeg

WhatsApp Image 2020-09-04 at 23.16.39 (1).jpeg

WhatsApp Image 2020-09-04 at 23.16.39.jpeg

WhatsApp Image 2020-09-04 at 23.16.40 (1).jpeg

WhatsApp Image 2020-09-04 at 23.16.40.jpeg

MBM27128-30_ HERO by Mania RJ_KUNFU MASTER By Irem Activision.BIN

Edited by pcrock
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Another doubt I have is:
The original dump I did (attached here) from the working cart does not works on Stella Emulator but works perfect in the cart. 
What is the reason?
I tryed to extract the first 8K from the original dump file (that I supose to be a game) and create a new file but that new file still not works on Stella.
Why the dump file from original eprom works in the cart but does not in the stella??
Thanks

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Those roms were modified to run on this board, because it implements a different bankswitching scheme compared to the original games.
They access address $FA0 for bank 0 and $FC0 for bank 1.


If you want to program the eprom with different games, you'll need to modify the roms as well for use with this board.

 

Stella doesn't yet support this as there were no known roms using these hotspots addresses before.

 

I drawn a schematic of the bankswitching logic using your pictures as reference (I had to guess a couple of connections, as some traces are not visible without desoldering the two logic ICs, but I'm quite confident that this is correct.

It's very similar to the scheme used in this other board (from brazil too), but this one uses more address bits, so the hotspots are a subset of those that trigger the bankswitch on that other board.

 

board.thumb.jpg.fac949c946a8bb2c9e66dc7d520c719b.jpgschem.thumb.png.06fe8d7b02d027a6201bdfb715f89e4c.png

 

 


Any address with A12=0, A10=1, A9=1, A7=1, A6=0, A5=1 cause a switch to bank 0
Any address with A12=0, A10=1, A9=1, A7=1, A6=1, A5=0 cause a switch to bank 1
Any address with A12=0, A10=1, A9=1, A7=1, A6=1, A5=1 may or not cause a bankswitch (undefined state of the NAND SR latch).

 

 

Thanks for sharing the dumps and pictures of the board!

 

Edited by alex_79
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3 hours ago, alex_79 said:

Those roms were modified to run on this board, because it implements a different bankswitching scheme compared to the original games.
They access address $FA0 for bank 0 and $FC0 for bank 1.


If you want to program the eprom with different games, you'll need to modify the roms as well for use with this board.

 

Stella doesn't yet support this as there were no known roms using these hotspots addresses before.

 

I drawn a schematic of the bankswitching logic using your pictures as reference (I had to guess a couple of connections, as some traces are not visible without desoldering the two logic ICs, but I'm quite confident that this is correct.

It's very similar to the scheme used in this other board (from brazil too), but this one uses more address bits, so the hotspots are a subset of those that trigger the bankswitch on that other board.

 

board.thumb.jpg.fac949c946a8bb2c9e66dc7d520c719b.jpgschem.thumb.png.06fe8d7b02d027a6201bdfb715f89e4c.png

 

 


Any address with A12=0, A10=1, A9=1, A7=1, A6=0, A5=1 cause a switch to bank 0
Any address with A12=0, A10=1, A9=1, A7=1, A6=1, A5=0 cause a switch to bank 1
Any address with A12=0, A10=1, A9=1, A7=1, A6=1, A5=1 may or not cause a bankswitch (undefined state of the NAND SR latch).

 

 

Thanks for sharing the dumps and pictures of the board!

 

Wowww!! Very thanks!! I have no words to thank you alex_79 !!!

I will remove the two ICs and post a picture to you ensure that all is ok!!

I am very sad about different bankswitching scheme in my circuit compared to the original games.

I can't understand. Why they do that instead to use original game schemes?

I did put a zif socket at this cart cause I did plan to use a lot of 27Cxxx with 8K games but is impossible to me modify originals roms to work with this cart! I don't know how to modify games. I would love to learn how but it appears to be very hard and complicated to me. 

Please let me know friend. Is possible to modify my circuit to became it able to work with original roms (mainly BeamRider, Pengo, Galaxian and Centipede)  or does exists any other way (like a software for exemple) that could modify the games for me?

Sorry if I boring you but I don't know much about programming (to tell you the truth I do know very very few)

Once more special thanks. 

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9 hours ago, pcrock said:

I am very sad about different bankswitching scheme in my circuit compared to the original games.

I can't understand. Why they do that instead to use original game schemes?

Because it was easier and cheaper to implement with standard logic ICs compared to the original scheme. In the original carts, the mask rom and bankswitching logic were typically integrated into a single custom IC, but that was only cost effective for large production numbers.

 

 

9 hours ago, pcrock said:

I did put a zif socket at this cart cause I did plan to use a lot of 27Cxxx with 8K games but is impossible to me modify originals roms to work with this cart! I don't know how to modify games. I would love to learn how but it appears to be very hard and complicated to me. 

Please let me know friend. Is possible to modify my circuit to became it able to work with original roms (mainly BeamRider, Pengo, Galaxian and Centipede)  or does exists any other way (like a software for exemple) that could modify the games for me?

Unfortunately, there's no an automated way to convert the games. It requires to "disassembly" the rom and examine the code. Some games are easy to convert just by changing a few bytes, others requires more extensive changes to the code. It really depends on the specific game.


Here is an example of standard "f8" bankswitching (used by most, but not all, of the 8k original games) implemented with 3 logic ICs:

https://web.archive.org/web/20150508151346/http://www94.pair.com:80/jsoper/bankswitch_f8.html

 

 

 

 

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Once more very thanks!! I want too much to get a way to make a BeanRider cart. 

I had a cartridge like that when I was a kid. It had BeamRaider, Tapper, Galaxian and Pengo and was my favorite cart but when I was 17 years old, I gave it to a friend! He promissed to return it to me when I asked for it back.  

 I really regretted it cause he says that lost my cart and I really want to play these games again with my daughter. Here in Brazil, unfortunately any cartridge (even a pirate) that has this game (BeamRaider) is very expensive !! There are many modified BeamRaider cartridges here to sell. I saw an advertisement for one of the same brand as that was mine that is the same brand I posted here (but with four games inside. It haves two switches and I do own a cart like that here with others 8k games. The circuit is identical but with one more switch. I tested and the any rom from two carts works on any of both circuits. Does anyone here have in their collection a BeamRaider rom extracted from some cheap cartridge that works on my circuit? Or does any friend here know how to modify my circuit to work with the original rom?

Thanks again!!!

Edited by pcrock
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2 hours ago, Thomas Jentzsch said:

If you split the 16K ROM into two 8K ROMs, they will work with the next Stella release (6.3).

 

Here are some screenshots.

MBM27128-30_ HERO by Mania RJ_KUNFU MASTER By Irem Activision.001.png

MBM27128-30_ HERO by Mania RJ_KUNFU MASTER By Irem Activision.001_1.png

MBM27128-30_ HERO by Mania RJ_KUNFU MASTER By Irem Activision.002_1.png

MBM27128-30_ HERO by Mania RJ_KUNFU MASTER By Irem Activision.002_2.png

MBM27128-30 H.E.R.O. (Mania).bin 8 kB · 2 downloads MBM27128-30 Kung-Fu Master (Irem Activision).bin 8 kB · 2 downloads

Very very cool!!! Where to download the latest Stella's version ??

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23 hours ago, pcrock said:

Once more very thanks!! I want too much to get a way to make a BeanRider cart. 

I had a cartridge like that when I was a kid. It had BeamRaider, Tapper, Galaxian and Pengo and was my favorite cart but when I was 17 years old, I gave it to a friend! He promissed to return it to me when I asked for it back.  

 I really regretted it cause he says that lost my cart and I really want to play these games again with my daughter. Here in Brazil, unfortunately any cartridge (even a pirate) that has this game (BeamRaider) is very expensive !! There are many modified BeamRaider cartridges here to sell. I saw an advertisement for one of the same brand as that was mine that is the same brand I posted here (but with four games inside. It haves two switches and I do own a cart like that here with others 8k games. The circuit is identical but with one more switch. I tested and the any rom from two carts works on any of both circuits. Does anyone here have in their collection a BeamRaider rom extracted from some cheap cartridge that works on my circuit? Or does any friend here know how to modify my circuit to work with the original rom?

Thanks again!!!

Here are some modified roms for Centipede, Tapper, Beamrider, Galaxian and Pengo:

fa0_conversions.zip
These should work with your board.

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50 minutes ago, alex_79 said:

Here are some modified roms for Centipede, Tapper, Beamrider, Galaxian and Pengo:

fa0_conversions.zip
These should work with your board.

WOWWWWW!!! I Will try it just NOW!!!!!
As I promissed I removed the logics ICs from the board and did a Picture for you. !
Once more I HAVE NO WORDS to thankyour attention with me!!!!

WhatsApp Image 2020-09-07 at 17.07.24 (1).jpeg

WhatsApp Image 2020-09-07 at 17.07.24 (3).jpeg

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12 minutes ago, Thomas Jentzsch said:

6.3 is not released yet and it may take some time.

Very Thanks for replying! 
Where is the official place to download the latest versions?
How to donate living in another country? I have interesting in donate if I can.

 

PS. I think I found the place and the way!
Thanks

Edited by pcrock
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3 hours ago, alex_79 said:

Here are some modified roms for Centipede, Tapper, Beamrider, Galaxian and Pengo:

fa0_conversions.zip
These should work with your board.

alex_79 my friend!!! You are a Genious!!!!Tapper is the only one rom that does not works!!! All the others appears to works GREAT!!!!
I converted my board to use a 27C256 and now it supports four 8K games! As you can see in the pics I sent it is working perfect thanks to you!!!
Now I have two identical boards that fits four 8K games each.
I think you've already helped me a lot!
I sent you a private message to thank you once more.

 

WhatsApp Image 2020-09-07 at 18.23.45.jpeg

WhatsApp Image 2020-09-07 at 19.26.55.jpeg

WhatsApp Image 2020-09-07 at 19.27.22.jpeg

WhatsApp Image 2020-09-07 at 19.28.14.jpeg

WhatsApp Image 2020-09-07 at 19.41.27.jpeg

Edited by pcrock
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The Tapper conversion runs in the coming Stella 6.3 if you manually select UA bankswitching. 

 

The problem seems to be the "bit $c6c6" code executed in RAM. The attached ROM should fix it.

tapper_fa0 (fixed).bin

Edited by Thomas Jentzsch
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3 hours ago, Thomas Jentzsch said:

The Tapper conversion runs in the coming Stella 6.3 if you manually select UA bankswitching. 

 

The problem seems to be the "bit $c6c6" code executed in RAM. The attached ROM should fix it.

tapper_fa0 (fixed).bin 8 kB · 3 downloads

I Will Burn an eprom just now and test it!! Will post the results here!
Special thanks Thomas Jentzsch!

Edited by pcrock
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4 hours ago, Thomas Jentzsch said:

The Tapper conversion runs in the coming Stella 6.3 if you manually select UA bankswitching. 

 

The problem seems to be the "bit $c6c6" code executed in RAM. The attached ROM should fix it.

tapper_fa0 (fixed).bin 8 kB · 3 downloads

Hi friend. Unfortunately the rom converted still not works. But now the issue is changed if compared to alex 79 version.

Now it remains in an Eternal looping trying to start.
Attached video is the present issue and the picture is the alex_79 version. Both still not working yet.
I am very thanks for trying to help me friends!

WhatsApp Image 2020-09-07 at 18.23.45.jpeg

Edited by pcrock
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On 9/5/2020 at 12:47 PM, alex_79 said:

Those roms were modified to run on this board, because it implements a different bankswitching scheme compared to the original games.
They access address $FA0 for bank 0 and $FC0 for bank 1.


If you want to program the eprom with different games, you'll need to modify the roms as well for use with this board.

 

Stella doesn't yet support this as there were no known roms using these hotspots addresses before.

 

I drawn a schematic of the bankswitching logic using your pictures as reference (I had to guess a couple of connections, as some traces are not visible without desoldering the two logic ICs, but I'm quite confident that this is correct.

It's very similar to the scheme used in this other board (from brazil too), but this one uses more address bits, so the hotspots are a subset of those that trigger the bankswitch on that other board.

 

board.thumb.jpg.fac949c946a8bb2c9e66dc7d520c719b.jpgschem.thumb.png.06fe8d7b02d027a6201bdfb715f89e4c.png

 

 


Any address with A12=0, A10=1, A9=1, A7=1, A6=0, A5=1 cause a switch to bank 0
Any address with A12=0, A10=1, A9=1, A7=1, A6=1, A5=0 cause a switch to bank 1
Any address with A12=0, A10=1, A9=1, A7=1, A6=1, A5=1 may or not cause a bankswitch (undefined state of the NAND SR latch).

 

 

Thanks for sharing the dumps and pictures of the board!

 

Pin 4 of U2 needs to be connected to something.  Floating inputs are not reliable.  Should probably be connected to pin 5, or to VCC.  Makes me wonder how this board ever worked, since the connections are confirmed after removing the ICs.

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45 minutes ago, ChildOfCv said:

Pin 4 of U2 needs to be connected to something.  Floating inputs are not reliable.  Should probably be connected to pin 5, or to VCC.  Makes me wonder how this board ever worked, since the connections are confirmed after removing the ICs.

Hi friend. Thanks for replying!!!
That circuit has been working perfect for the last 37 years exactly as described in the schematics drawn by alex_79.?

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"Works" and "Correct" are not necessarily the same thing.  From Fairchild's TTL design notes:
 

Quote

Unused inputs on TTL devices float at threshold, anywhere from 1.1V to 1.5V, depending upon the device and its family. While this usually simulates a “high”, many application problems can be traced to open inputs. Inputs floating at threshold are very susceptible to induced noise (transmitted from other lines) and can easily switch the state of the device. A good design rule is to tie unused inputs to a solid logic level.

 

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7 hours ago, ChildOfCv said:

Pin 4 of U2 needs to be connected to something.  Floating inputs are not reliable.  Should probably be connected to pin 5, or to VCC.  Makes me wonder how this board ever worked, since the connections are confirmed after removing the ICs.

You're right, and I'd have expected pins 4 and 5 to be connected together too. But the pictures with the IC in place showed no solder on pin 4 on either side of the board, and another similar PCB documented a while ago leaves an input of a used gate floating too, so I thought they did the same here.

Note that in both cases they could have connected the floating input to a pin right next to it.

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18 hours ago, pcrock said:

Hi friend. Unfortunately the rom converted still not works. But now the issue is changed if compared to alex 79 version.

Now it remains in an Eternal looping trying to start.
Attached video is the present issue and the picture is the alex_79 version. Both still not working yet.
I am very thanks for trying to help me friends!

 

WhatsApp Image 2020-09-07 at 18.23.45.jpeg

Another try...

tapper_fa0_v3.bin

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