J-PAC shift function working oddly

[Hammerfist]

I've had J-Pac in my cab for a while now and it's been working as it should, until today when I tried to "insert coin" (player 1 start + sw 1) and nothing happened. First I thought it might be the player 1 start button having a bad connection, but when I ran the winipac test mode, it showed that it's connecting. I did notice a weird behaviour with this as well, as the test showed key press for "1" only when I released the pl1 start button, instead of showing the pressed key when button is pressed. I'm thinking this is because of the shift-function with the pl1 start button. Anway, when I tried the shift-function with pushing pl1 stick to the left and right, it worked as it should, showing the default enter and tab as being pressed.

I tried uploading the button info again to the J-pac, but no help. Then I tried to set some other keys to other buttons for pl1 and pl2, but the same problem was with them as well, as the test mode showed no input (testing from keyboard, it worked ok). So now it seems, that for some reason, the shift function is not working with the buttons. Any help with this?


It seems that contrary to my earlier believe, I hadn't booted the system to try to repair the issue. Everything is working now as it should. Too little sleep I guess . Trash away, I can take it

Just to make sure, everybody understand this : There is nothing wrong with the J-Pac, it's a great product. So don't let this make you think otherwise!

Thanks!

[pinballjim]

I've never had much luck with the shift functionality on JPACs. 

If you're just running MAME, there's really no need for it anyway - you can set things in MAME to only work with simultaneous button presses.

[Hammerfist]

Hi PBJ. How do you mean? I'm running quite a few emulators though, but thus far MAME has been the only one where I've needed the shift function, so I'm interested to hear what you mean. Thanks!

[AndyWarne]

Its true that MAME can be configured for "AND" combinations of keys. But there are limitations to this.

For example if you replicate the I-PAC shift combination Start1 + P1SW1 = coin, as soon as you press the Start1 button the game will try to start because the "primary" key is sent, then the shifted "coin" key will be sent.

This does not happen using the I-PAC method, the primary key is not sent, only the shift combination key.

This does not cause issues with some key combinations but does with others.

[Hammerfist]

Ok, I hadn't thought about that and see no need atm, but that's good to know.

It seems that my computer is putting the J-Pac out of whack sometimes, now that I've been building my cab. I'm thinking that it happens when I have to turn my monitor off and on while my PC is running. Not something I need to do when the cab is finished. Trying to avoid it, but there's been a few "must" situations.. Some kind of "back fire" maybe.

Thanks Andy!

[pinballjim]

For example if you replicate the I-PAC shift combination Start1 + P1SW1 = coin, as soon as you press the Start1 button the game will try to start because the "primary" key is sent, then the shifted "coin" key will be sent.

I've only found this to be an issue with the USB joystick encoders.  The obvious solution to your scenario is to press and hold Player 1 Button 1 before you hit start, though.  I physically alter my JAMMA harnesses when I'm using a JPAC and rewire player 1 start to one of the screw terminal inputs on the board.  That shift functionality has been nothing but trouble in my experience.

I'm thinking that it happens when I have to turn my monitor off and on while my PC is running.

Nope, you've just got a dud JPAC.  It happens.

[AndyWarne]

Ok, I hadn't thought about that and see no need atm, but that's good to know.

It seems that my computer is putting the J-Pac out of whack sometimes, now that I've been building my cab. I'm thinking that it happens when I have to turn my monitor off and on while my PC is running. Not something I need to do when the cab is finished. Trying to avoid it, but there's been a few "must" situations.. Some kind of "back fire" maybe.

Thanks Andy!

One possibility is monitor grounding. Is the monitor chassis permanently connected to the power cord ground? It should be, even if its turned off. If the only ground path is the ground wire on the video connection this might not be sufficient. When the monitor is turned on, the degaussing and the power supply startup cause a large current to be induced into the ground which must have a good path to directly discharge through.

[Hammerfist]

One possibility is monitor grounding. Is the monitor chassis permanently connected to the power cord ground? It should be, even if its turned off. If the only ground path is the ground wire on the video connection this might not be sufficient. When the monitor is turned on, the degaussing and the power supply startup cause a large current to be induced into the ground which must have a good path to directly discharge through.

Hmm, the cabs wiring (not counting what I've added) is basically as it was when it left the Atari factory, so I hadn't thought about that earlier. Power cable for the monitor has neutral and live, but I didn't find a ground wire when I had a quick look yesterday. Of course the cab has ground wire and it's attached for example to the switch, that powers the monitor.