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johnnywc last won the day on May 17

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About johnnywc

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    River Patroller
  • Birthday 03/05/1968

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  1. Hello there! As we near the release of ZK, I've been going through the old development thread and I completely forgot to answer your question - sorry about that! Yes, the ZK high score table will display scores up to 99,999,999 by removing the rank #. Hmmm, that's strange. I'm pretty sure on level 1 the net is the 2nd to the last item that appears (one more root beer appears before the end of the level). I haven't seen this happen over here but will keep an eye out for it. Thanks! John
  2. Thanks for the offer! Nathan T. aka @gauauu is handling the PCB and enclosure design; I'm sure he would welcome the assistance.
  3. Good news! I received both 7800's from @McCallister today and they both work flawlessly with the QT, so I think we can consider that one solved (especially since I distinctly recall it working on my 7800 too). Turns out my 2nd controller port on my 7800 isn't working now either, so there's a bunch of things wrong with it. Anyone have any recommendations for a service that can repair a 7800? So as long as we don't need pullups on the joystick inputs (and it sounds like we don't), we're good to go! Nathan T. @gauauu is itchin' to get the design finalized and put into a case for a hopeful holiday release! Thanks again everyone for the help! John
  4. Okay great, thx for the info, that makes sense about the mux. Okay, so since the mux is really just a relay, there really isn't a need for a pull up resistor on the joystick inputs before the mux, right? It sounds like the pullups in the Atari will take care of it then. I'm still a bit confused why the measurement at the joystick inputs fluctuates between 5.2V to 3.6, but perhaps that doesn't matter since it's above 2.0V? Thanks again! John
  5. AtariAge member @McCallister has graciously offered to send me a couple 7800's to test with and they should arrive tomorrow; fingers crossed they just work and it's my 7800 that has the problem. 🤞 If none of them work, I'll assume my 7800 is fine and then we'll need to explore options to hopefully resolve the issue by updating the design. 😕 In the meantime, above I mention the voltage I'm measuring at the joystick inputs when they're open and it's between 5.2V and 3.6V. Is this okay? I added a pull up resistor bank (10K) and the voltage stays between 5.1 and 5.5 volts. Do you recommend that we add pull-up resistors to the joystick inputs? I'm worried that when it dips to 3.6 volts it may register as a low to the mux, but then again that may be well within the tolerance. Any suggestions are welcome! Thanks, John
  6. Wow! Great job Nathan! I have not achieved the coveted 1,000,000 point jump... yet!
  7. Hello there! Sorry for the late reply.... We are on Release Candidate 7 and the final version will be available on cart in the AA store soon!
  8. We're working on it now Steve! I just finished adding in co-op mode that will allow you and a friend to battle together! We're still testing it, but here is how it works for now: the players are working together to achieve one high score and they share the pool of reserve lives. two mutants (different colors) start the wave in the middle of the screen each player independently controls a mutant with their controller. Note: for now, only single joystick control is supported for each player, but the final version will allow BOTH players to each use two joysticks (one to move, one to fire) using the QuadTari to balance the game play, both players have a pool of 4 shots total that they can fire at any one time (meaning if one person is shooting, they can shoot 4 missiles; if both players are shooting, they each will fire as long as there are < 4 shots on the screen) half of the enemies pursue player 1, the other half pursue player 2. If one player is removed from the wave after being killed, all enemies will pursue the remaining player. If one player is killed during a wave: On Novice, the player stays on the screen in a zombie state (cannot move or fire). If the other player touches them, they are revived (invincible for 2 seconds). If the second player is killed before they can revive the first player that was killed, a life is lost and the wave resets with the remaining enemies. On Standard, the player is removed from the game. They will return at the start of the next wave or if the other player is killed during the wave and there are reserves left. On Advanced, the team loses a life and the wave resets with the remaining enemies (like normal) We hope to post a demo of co-op mode soon for people to test out and give feedback. Thanks, John
  9. Hello all, Looking for a working NTSC Atari 7800 system for testing. I live in CT so something close would be preferable. Thanks! John
  10. Thanks, I'll give it a shot, but I must be honest that 90% of what you said doesn't make sense to me. 😛 I'm sure once I open it up and find some schematics online it will be a little more clear. In the meantime, I'm going to try to acquire another 7800 to test to see if this is a problem with the QT or my 7800. Thanks again! John
  11. Update: I modified my test program to set bits 2 and 4 of SWCHB to '0' (as it seems that they default to 1) and the voltage measurements for pin 6 on the Atari are the same with no buttons/1 button/2 buttons pressed as the bits being set high. 😕
  12. No worries, I was able to bring it up on my phone. Okay, I did some measurements of pin 6 on the Atari and they are the same with my old multi-tap app that doesn't set the bits of SWCHB and the new app that sets bits 2 and 4 high for SWCHB: No buttons pressed: ~5.40 V one button pressed: ~5.00 V both buttons pressed: ~4.63 V I think I may be setting the bits wrong; should they be set to '0' and not '1'? The reason I ask is that I'm displaying the value of SWCHB in both applications and for both they all display 00111111 (the two 0's are for the difficulty switches that are in the B position), so it seems that bits 2 and 4 default to 1 even if you don't do a write to SWCHB. I did measurements for pin 6 at the Atari on the working 2600 and they are the expected values of 5.52V (no buttons pressed), 2.46V (1 button pressed) and 0.15V (both buttons pressed). I'll modify the program to write 0's into bit 2 and 4 and see if that makes a difference. Thanks! John PS Regarding the other question about the "floating" voltage I'm getting measuring the inputs at the joystick that I mentioned above. It looks like it fluctuates slowly between 5.2V and 3.6V when the switch is open. Is this okay? Do you recommend a pull-up resistor on the joystick inputs? I added a 1M (I'm sure smaller values would suffice too) pull-up resistor network (we had these in the previous designs) and the voltage now fluctuates between 5.5V and 5.1, but I'm not sure if it's needed. Thanks!
  13. Okay, that makes sense, and I do recall a game using the bits as RAM, although I didn't realize it was the *first* 2600 game! 😮 Great thx for the link.. unfortunately my Norton antivirus says it's a 'bad site' and I can't open it. 😕 Okay, I put this code in the beginning of my test program to disable the transistors: lda #%00010100 ; bits 4 and 2 (0 based) sta SWBCNT ; enable for output sta SWCHB ; disable transitors Unfortunately, this didn't seem to make any difference with the buttons working on the 7800. I only had time for a quick test but I will measure the voltage on pin 6 to see if it goes any lower when the button(s) are pressed vs. the readings I got with the transistors enabled.
  14. Okay, I'm not exactly sure what that means. SWCHB is input only so I don't think you mean that, unless it can be configured for output on a 7800? I checked and bits 2 and 4 are unused (0-based) so maybe that's what you mean? Sorry for the confusion!
  15. Thanks for the info! I figured there was something different between the 2600 and 7800 that was causing the issue. I'm 99.9% sure it was working on a 7800 before. My test environment has an un-modded 2600 hooked up to a CRT, an S-video modded 2600 that's hooked up to a CRT and an AV-modded 7800 hooked up to my 1702. I distinctly remember doing tests on all 3, most notably the 7800 because the 1702 is near my computer where I was modifying the test program to add in the color/bw and difficulty switch options. I don't have 7800 games that aren't in storage so I'm 100% sure the tests were with 2600 cartridges (the Harmony cart, my test program and the original 2K Basketball game, to be exact). I know the button was working or I would not have been able to select the test program from the Harmony cart. Hmm, that doesn't sound good. Any electrical issue that could have caused it to go from working to non-working (ie. a transistor/capacitor/resistor in the 7800 got fried with the lightning issue I had)? Is there anything we can put between the mux and the Atari that can assist in pulling the transistor-based pull up to 0V?
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