Debounce and DevOs .2 question

[SIO2]

I tried the smasteroids demo from 7800bas by uploading it to my DevOs .2 modded 7800. I get a strange result.

 

It works fine except the ship doesn't fire if I use either an Atari 7800 joypad or a modded Nintendo pad. Both controllers are known to work and play other games on this same console.

 

The ship does fire though if I plug in an epyx 500xj, or a gemstick or a wico stick.

 

I have been playing with the debounce routine in smasteroids but keep getting the same result.

 

Any ideas why this is or what might be done to get it to accept most controllers?

Edited March 3, 2015 by SIO2

[+RevEng]

Its only part of the puzzle, but when 7800basic sees a single button joystick button press, it turns off 2-button mode for that stick and reverts to 1 button mode. This uses a different register for reads.

 

Have you tried any other 7800basic samples? e.g. the Adventurer demo sets the background blue or red, depending on which button was pressed.

[SIO2]

Its only part of the puzzle, but when 7800basic sees a single button joystick button press, it turns off 2-button mode for that stick and reverts to 1 button mode. This uses a different register for reads.

 

Have you tried any other 7800basic samples? e.g. the Adventurer demo sets the background blue or red, depending on which button was pressed.

I tried Adventurer. Same result. My single button joysticks work but my control pads don't fire. The control pad directions all work. Just no fire buttons.

 

I tried a 7800 proline joystick. No fire in 7800bas games. So, it looks like it is a two button vs one button issue.

Edited March 5, 2015 by SIO2

[+RevEng]

Yeah, no doubt. It sounds like something is tripping the one-button protection... plugging a single button joystick into a 2-button game that doesn't have this protection causes a short in the console.

 

Can you try the utility cart and run the controller test? If you could reporting all of the values on the bottom half of the screen (without buttons pressed) would help.

[SIO2]

All controllers produced the same result as attached image with no buttons pressed.

Interestingly if I pressed the left button on a 7800 joypad, inpt1 becomes 80 and when I release the left button inpt1 returns to 00 but, inpt2 begins to toggle. The display updates very quickly so I am not sure of the value but it looks like inpt2 toggles from 00 to 08 or 0A or 0F (something with a bar on center of character). If I press the left button again inpt2 stays on 00.

 

Actually I just figured this out. I had been using a controller extension cord before (was not plugged in for the utility cart tests). When I try smasteroids demo without the extension cord, it works.

 

Sorry. I guess the extension cord only expects 2600 one button controllers.

Edited March 5, 2015 by SIO2

[+RevEng]

Glad it was a mundane explanation.