pcrock

Hi friend, thanks again. Please tell me what you think. As you can see in the pics I attached, this Board is locked at this time to run two 4K games but it is designed to run till four 4K games. It will works without any inverter with a 27128 ??? The red pointed places in the pics below is the switches to select the games.

Woooww! I will burn an Eprom just now to test it!!!! Thanks again!!!

Hi friend. Once more thanks for replying. I know and I understand you are right about the TTL information you told us so I'm going to change my answer. What I meant is that this cartridge has been running Atari games for the past 37 years without ever failing. Which means that for this purpose, at least, this circuit works correctly in the way it is designed even if it is a weird thing. I have another older PCB whose design is also like this with these floating pins. But now you advised us about the question, I found a lot of other circuits here that matches exactly as you sayd! It haves the pin 4 and 5 conected together ! Once more I hane no words to thank you all for helpping me here!

Do you (or some other friend here) understand something to tell me about the Kankaroo cart I placed at the beginning of this post????

Here there were several like this !!

You are absolutely correct! Everything you just said, accurately describes the Brazilian computer industry in the 70s and 80s! Very few resources, little money and a lot of creativity, intelligence and cleverness! Here we have a famous saying: "A necessidade é mãe da solução" that means something like "Needing is the mother of the solution!"! Nowadays we have better resources than in those days, but unfortunately it is expensive when compared to countries like USA, Canada, Japan and part of Europe.

I would like to ask a question about below cart. It is a 2 in 1 4K games selected by a switch. My quest is: Shouldn't there be an additional inverter circuit for this cartridge to work properly? Where is it ??

" DIGITAL " Game Selection!!! Another strange to me Dynacom 2 in 1 2K games. That cart haves an Eprom and one more IC. Both of them were sanded and is impossible to see the chip numbers to identify it!! Two electrolytic capacitors 1000uF x 10v and 220uF x 10v. The games are Freeway and Skiing (both from Dynacom). The game you want to play is selected by touching the metallic contacts (red pointed in the pic I take) That is a Brazilian cart.

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.😄

AMMMMAAAAAAZING GAME!!!!!!!!!!!!!!!!!!!!!!!!!!

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 Video 2020-09-08 at 18.50.20.mp4

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

Here I have another curious thing. A one chip 8in1 cart. All games is 2k ones.

I own a Dynacom 8k Kangaroo cart that I think is a curious thing. It haves two eproms. What is the reason for that?? Why two ones? All ICs numbers (even the logics) were sanded and is impossible to me to know more. I have others Kangaaroo carts that uses only one eprom. Would be exactlly a half of code on each of them? I yes, why?

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.

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

YES! But this board can easily be converted to four games by adding one more switch. To tell you the truth I do own another identical board with one more switch that runs four 8K games

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!!!!

Digikey is very very expensive way to get parts!!!

Are you talking about Cathode Ray Tubes? I can't understand about target of your message.

Unfortunatelly I think that MK4027N will not work. Maybe with some changes in the circuit but I am not sure. Please read the post I sent.

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

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!!!

I bet on a PPU issue too. Do you have the schematics to show us?

Hi friend. I don't know if it could help you but please take a look here