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Everything posted by djmips

  1. Since you watched the AGC restoration series you might know this but Mike Stewart's GitHub has the source to his gate accurate replica of the AGC. https://github.com/thewonderidiot And he has a series of blog posts. Good read. http://mikestewart.hcoop.net/
  2. Have you seen the Bob Ross of computer engineering? Ben Eater's videos are great even if you already know everything. And some fun thing I found recently. You should probably whip through it just for fun. http://nandgame.com/
  3. djmips

    ATAN2 in 6502

    If someone's looking for something actually useful. http://www.dustmop.io/blog/2015/07/22/discrete-arctan-in-6502/
  4. That's nice to hear you are coming up to Canada! I almost took a job in Montreal myself - great city. I was hoping to bump into you at PRGE but maybe next year! Good luck at the new job. Your latest game looks super. - David
  5. Fantastic! Of course I like button for jump and up for shoot as well. But some people are going to want to swap to "up for jump and button for shoot" (if they don't have a Genesis controller). So consider putting in that as an option - menu or difficulty switch perhaps. I'm always abusing the difficulty switches; it is confusing but allows configuration without adding a menu and it's sticky.
  6. djmips

    Hunchy II

    Hunchy 2 was the one home brew that I and my kids played more than any other home brew title on the 2600. Hope you're doing well Chris! It's good to see you around these parts so many years later. - David
  7. Good points about the schematic. Elsewhere in this thread you'll find a PCB image of the Mod and it's essentially what you're asking for. The PCB layout is what I referenced to build mine but I assembled mine on a proto board.
  8. If you can ignore audio for the purposes of explanation, for this Mod, the three wires to connect from the 2600 are. VIDEO; +5 VOLTS; GROUND. The output of the Mod is just Video and Ground to a female RCA jack or male RCA cable. The three connections are all visible from the component side of your 2600 motherboard. All three are detailed at the site I linked.
  9. cut/paste mistake. Jr. mod that I used: https://www.thefuturewas8bit.com/index.php/2600jr_comp_mod 4 switcher version https://www.thefuturewas8bit.com/index.php/2600_comp_mod If you need another model it might be on that site.
  10. Re: Component Removal I used the following instructions. https://www.thefutur...2600jr_comp_mod For 4 switch he also has. https://www.thefutur...p/2600_comp_mod
  11. Read the entire thread. The 1477 is a 5K trimmer potentiometer set to 1477 ohms for simulation. You just need to either put in a trimmer pot there. I didn't have a trimmer pot around so I just removed the 1K and added a 3.3K - my hack - I eventually intend to measure it's output on a scope to trim it correctly.
  12. The C7 would be attached to either side of the resistor but you don't have to put on C7, the designer actually left it out of the final version.
  13. For help in understanding an electric schematic check this out -> https://learn.sparkfun.com/tutorials/how-to-read-a-schematic
  14. I wired the video out to the existing RF output - It's connected in the upper right in the RF area. Yellow wires are video. The audio is wired underneath and I added a second RCA jack so I can use RCA cables to my monitor. Wires are too long, I will shorten them later. I'm not the best at the case mods. Too impatient! I know you can't see the wires and removed components because they are under the shield in myphoto. I used the following instructions. https://www.thefuturewas8bit.com/index.php/2600jr_comp_mod For 4 switch he also has. https://www.thefuturewas8bit.com/index.php/2600_comp_mod
  15. I just put this together last night on an Atari Jr and it worked first time and it works great! Thanks @simon.plata! Got to see my old Mega Man prototype game running again for the first time in a long time on my 1702 composite display. I used 2% resistors except for one 5% which I graded and selected with a multi-meter as you suggested. I trimmed manually and didn't put in a variable resistor into the circuit. I did not grade the transistors so I guess I was lucky or not a perfectionist. I don't have a scope so I didn't check the peak to peak voltage on the output. I have brightness / contrast on the front of the 1702 which I did tweak slightly. I hooked the video / audio output to cables poking out the back but I intend to convert the RCA RF output connector to video output and add an audio out as well. I'll add pictures later. The video looks awesome! Now this will help me on some 2600 development which I have been returning to finish up a couple of old projects.
  16. I was just going over some old posts of mine today and I forgot that Pinball Construction Set (6502) source code was released on GitHub https://github.com/billbudge/PCS_Atari800 https://github.com/billbudge/PCS_AppleII
  17. It is a game that works with paddles. In stella you have to set it up the controller port to be a paddle and then the two axis of the mouse are the left and right paddles. It's quite awkward and doesn't really work that well. * You also have to have the right difficulty switch set for left or right port. Ideally you would play this on a real Atari with Paddles. * Maybe Stella supports two mice for left and right paddles but I don't know if it's possible.
  18. Someone pointed out they saw a flash of the ball at the net when a point was scored. So this is a fix for that. It turned out the call to setup display was before the move ball so simply switching them around was the fix. Before there was a one frame delay on display outputs from the move ball routine. I'd also like to note that vdub_bobby is the co-author of this little project. apong.bin
  19. I realize now this was actually a bug you were reporting. It's fixed now.
  20. OK here is the update. Add feature that right difficulty switch controls left/right paddle port Fix bug where when the ball gets stuck. If the ball hit the paddle in the middle right after it should have bounced off the bottom of the screen the ypos would end up being incorrect and stuck. The fix is to always do the math to fix up the ball position immediately after inverting the yspeed instead of waiting for the next frame update to take care of that because an intermediate collision check with the paddle could zero out the y velocity and it would never be able to be inverted and correct the position. TLDR - paddle switch on right difficulty switch: Keep the ball in legal area at all times. BTW - the Left difficulty switch controls whether the game goes to 11 or 15 which was a switchable option on the original Arcade Pong. This was already in my code and I did not change it. -DG ROM here apong_2019.bin
  21. So this weekend I did manage to dig out my Atari Jr., Harmony cart and found I had to solder together a power supply AND a video cable (I considered going full bore and making the composite mod heheh - later) - I found all the source code I could find and I put them up on GitHub - https://github.com/djmips/APong Proceeding from that I had to start reasoning over my old code. Turns out there's still some annoying bugs that need to get fixed. I wonder if I should make it work from either port with a switch? Maybe the difficulty switch.
  22. And while I'm here, I'd like to officially set fire to the ridiculous animosity towards bumping old threads. - Who cares!
  23. OK sounds good. I can get to it this weekend.
  24. You deserve it! I loved your idea and name from the very first moment I heard about it. Such a fun concept.
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