Button Layout Help

[Moleburt]

I am in the process of designing my cabinet/control panel. I realized that I had planned a CP that had a total of 34 buttons, p1 7, p2 7, p3 4, p4 4, coin and start for each, and 4 function buttons (pause, exit, load, save), but I then realized that the Ipac ultimate only supports 32 buttons, plus 4 joysticks. My plan for p1 and p2 was to do like the 7 button layout with the neo geo style 4 on the bottom and then 3 on the top. Since I need to remove buttons, I could do a few things.

1. Remove the 7th button from p1 and p2 (I just like the idea of having neo geo games play with a traditional layout)

2. Only have 2 function buttons (exit, and one other, then use the Ipac shift options for the other functions needed)

3. Wire the 7th p1 and p2 button to one of the top buttons so they function as one in the same, but aesthetically will keep the look. (I don’t think this would interfere with anything else since the 7th button would only be used for neo geo games).

Any input would be greatly appreciated!

[Nephasth]

1 & 2

[PL1]

use the Ipac shift options

Be sure to disable the Menu (TAB) shifted function so kids and/or drunk friends don't get into the menu system and mess up your setup.   

3. Wire the 7th p1 and p2 button to one of the top buttons so they function as one in the same, but aesthetically will keep the look. (I don’t think this would interfere with anything else since the 7th button would only be used for neo geo games).

Wiring the 7th button in parallel with an admin button like Coin1 means both buttons will output the same keystroke and trigger both assigned functions.  Every time you press the 7th button, it will register as both P1B7 and Coin1.

The way around that is to use blocking diodes on dedicated admin buttons to trigger shifted functions.

Randy posted this great diagram here on GGG.   
- X and Y switches are player buttons or joystick inputs. (unshifted functions)

- Shazaaam! switch is P1 Start (shift button)

- The two switches on the right are the dedicated admin buttons used to trigger shifted functions with a single button press.

- When you press "X", ground is applied to the pink wire going to Input X and to the anode (+) of the pink wire diode.
-- Ground on the anode = not forward biased.  Diode doesn't allow current to flow through it. (blocked)
-- Normal output for "X".

- When you press "Shazaaam! + X", ground is applied to the cathode (-) of both diodes.
-- Ground on the cathode and 5v from the Shazaaam! and X inputs = both diodes forward biased.  Diode allows current to flow through it.  Ground applied to both Shazaaam! and X inputs.
-- Shifted output for "X".
-- Ground is also applied to the anode of the blue wire "Shazaaam! + Y" diode = not forward biased.  Diode doesn't allow current to flow through it. (blocked)



Add as many shifted function buttons as you want/need.

You can still manually trigger shifted functions.  P1 Start + P1B1 = Coin1.

Any 5v diode will work.  The 1N4001 is common and inexpensive.   


Scott

[BadMouth]

2 - The only admin button you need is exit.  Pause is borderline, but acceptable.

Don't use the shift functions.  Use a wireless keyboard for maintenance and the occasional load/save.  Hide the keyboard when guests are using it.

[Moleburt]

I think I'm going to go with option 2, and just have 2 function keys. I don't think for most of the games I will be playing that having a save/ load button will be necessary. I was also considering purchasing a iPac2 and using that to wire my function keys into, I couldn't find any other USB encoder that was cheaper, but I also wasn't sure if you could use a iPac Ultimate and iPac2 together, I know for what I'm considering using it for people will probably say it would be pointless, I just had my initial vision in my head for everything and once I set my mind to it I have trouble convincing myself of changing my plan, but only having 2 function keys shouldn't really change anything, I'm just stubborn.