peteym5 Posted July 10, 2022 Report Posted July 10, 2022 I found out that 7800 Basic looks for these controller functions by watching for input from the directional control bits that would be impossible for a joystick itself to produce. Like pressing left+right+down at the same time. But I had at least one of controller in my history of video games that somehow tripped 3 pins because of the layout. I think having pause, reset, and select on the controller would be great, but I am not aware that anyone made such a controller for the 7800. Anybody here knows something about these? Quote
CrossBow Posted July 12, 2022 Report Posted July 12, 2022 Well, I do know that controller + button combos can be used to at least activate the Pause function. A recent homebrew does this for instance and doesn't require any hardware modification. Aside from that, I was able as a test to essentially wire up the same modification that is done on the SMS along with adding a button to the controller to give remove pause function. I replicated this on my test bed 7800 but never did anything beyond testing if it could be made to work. But something similar would likely be possible for most of the functions but require some sort of controller to be added to handle the different input combos to additional logic added to the 7800 to route it where it needed to go. Quote See what I'm up to over at the Ivory Tower Collections: http://www.youtube.com/ivorytowercollections
peteym5 Posted July 14, 2022 Author Report Posted July 14, 2022 I got word back that these are do it yourself hobby built game controllers, and never sold by anyone. What they did was use left + right + up to indicate pause and left + right + down to indicate reset. But this is something that should be disabled by default because most developers want their stuff to run on stock hardware. With all the different models of controllers being used all these years, some could trip 3 switches at the same time. I had one joystick doing to me, and I just ordered another one on eBay. Quote
CrossBow Posted July 15, 2022 Report Posted July 15, 2022 Well the specific kit I used and made work on my 7800 test unit was the same kit used for the SMS controller pause kit. It just uses the L + R combo to a logic gate which, in turn then sends the signal to the pause pin on the CPU. On the 7800 I did the exact same thing. Now, it does require some diodes to be installed on each of those left right controller lines so that pressing right or left by themselves doesn't feedback and actually do the impossible combo. I also tend to add another diode from the pause signal so make sure that is one way. This way, the L + R combo doesn't interferer with paddle controller reads or cause the system to think a paddle controller is connected. I found that out the hard way with my Harmony cart when I originally had it wired up to use Up + Down. So using the Left + Right combo worked well in the case of the 7800. But like I also stated, you can program simple combos from the controller to do similar functions. The one homebrew I know doing this I believe uses up + button 2 and that brings up a map screen in the game. During the map screen the game is also paused, but using the actual pause button also brings up the map screen in the same fashion. In fact, when the game was in early development, it only used the pause button and that was why I made a remote pause function on my controller with an extra button. I was using a modified NES controller so I had my pic of the Start/select buttons as my extra button for the impossible L+R combo in this case. Anyway, the programmer eventually found that you could trigger pause on 7800 games with controller combos so he did that and it made the 3rd button setup no longer needed. Quote See what I'm up to over at the Ivory Tower Collections: http://www.youtube.com/ivorytowercollections
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