Encoder Default Settings Conflict

[PL1]

I know it's easy to reprogram and I'm NOT asking this to call anyone out -- just curious if there is a good reason for the fairly obvious mapping conflicts. 

MAME Player 2 Button 5-8 default keys are undefined and Player 3 directional default keys are I, K, J, and L.

Why do IPac2, IPac4, and KeyWiz use I, K, J, and L for Player 2 Button 5-8 default keys?   

Why does the IPac4 use I, K, J, and L for Player 2 Button 5-8 and Player 3 directional default keys? 


Scott

[RandyT]

As the MAME P2 5-8 keys are, by default, undefined (as far as keys are concerned), they can really be anything the user wishes them to be.  In the case of the KeyWiz with 40 inputs, a 4-player panel is a real possibility.  In that event, those inputs for P3 are already defined, and the user can simply select any of the other unused ones for the P2 5-8 keys.  For a 2 player panel, using the defaults from Player 3 really doesn't matter, as there wouldn't be one to conflict with.

It's all relative anyway, as MAME doesn't care.  It doesn't even look at the definitions for Player 3 unless Player 3 is actually playing.  In other words, there's no conflict unless the user creates one through lack of planning for a given panel requirement, and even then, it's simple to fix through MAME's setup.

[PL1]

As I said, easy to work around, but it still doesn't make sense that both companies would have randomly picked the same conflicting settings.

I figured that either:

1. The default keys for MAME were changed after the KeyWiz and IPac came out

2. The first one released had the conflict and the second one just followed the pattern


Scott

[JDFan]

I think part of it is the games themselves IIRC most 3 or 4 player games do not use more than 4 buttons so that leaves the 5-8 player 2 buttons unused opening up those keys for use as the 3rd player defaults. (which could be how those were picked in the first case and as mentioned the second company just followed the pattern for consistency.) 

[Nephasth]

Gamepad encoder.

[PL1]

I think part of it is the games themselves IIRC most 3 or 4 player games do not use more than 4 buttons so that leaves the 5-8 player 2 buttons unused opening up those keys for use as the 3rd player defaults.

You are correct about 4 player games not having more than 4 buttons, but these encoders were designed to work with MAME which means that P1 and P2 would need up to 6 buttons each.

Have you ever seen a 4-player MAME build where P1 and P2 only had 4 buttons?

All the ones I remember had at least 6.


Scott

[RandyT]

You are correct about 4 player games not having more than 4 buttons, but these encoders were designed to work with MAME which means that P1 and P2 would need up to 6 buttons each.

Have you ever seen a 4-player MAME build where P1 and P2 only had 4 buttons?

All the ones I remember had at least 6.

It seems like you may be creating issues in your mind where none truly exists.  If you are configuring a panel for 2 players, and MAME requires you to set up P2 5-8 when using a Keyboard encoder (which it does), it will never make any difference what P3 (or any other player controls outside of P1 and P2) is assigned to.  The physical location of the connections on a PCB is of no consequence.  With a 4-player panel using the same encoder, one could simply use those existing definitions for the controls to which they are assigned by default, and select any random inputs for the ones which must be re-assigned for P2 5-8 anyway.  The only reason this is the case, BTW, is because MAME has adhered to it's legacy default assignments which were designed so many years ago to take maximum advantage of the limited controls available at that time; a stock, matrixed keyboard and simple gamepads, and not, superior to those devices, 40 input, non-matrixed, specialized input controllers.

You have to keep in mind that controllers like the KeyWiz are primarily intended for a 2 player setup, with the real option of pushing it to a 4-player panel controller if so desired.  The latter, by definition, requires more configuration in the software and planning.  Regardless, there are no "conflicts" in the default mappings.  It's all about how an individual both wires the panel and/or configures the software for their individual  purposes.

This discussion is starting to remind me of a comment made by someone in the past about how assigning a gamepad button input to a digital joystick switch seemed wonky to them, while being absolutely fine with the same switch being connected to produce a "Q" key when activated .  It's all relative, and it makes no difference to MAME.

[PL1]

   I'm NOT asking HOW things work.  How =/= why. 

I'm just asking If there was a logical/historic reason for a choice that seems to be counter-intuitive today.

The seemingly random QWERTY keyboard layout was originally adopted to reduce typebar jams like this on old manual typewriters.



Knowing that, the QWERTY layout makes more sense.

I remember reading somewhere that MAME used Control, Alt, and Shift keys to work around the limitations of some keyboard encoders that would only register a certain number of keypresses since those three weren't included in the limitation.

By knowing that limitation/work around and looking at a keyboard, the MAME defaults make sense.

I'm just asking about the logical/historic reasons, if any, behind I, K, J, and L being chosen as the P2B5-8 defaults for encoders.

If the answer is, "Andy pulled them out of thin air without considering 4-player panels and inertia has kept the settings that way," then that's the answer.

No need to treat me like I have some kind of irrational obsession for simply asking if there is a logical/historic reason for what appear to be counter-intuitive default settings. 

In the old story, it was a young lad that pointed out that the Emperor had no clothes -- I figured there might be some unknown Lady Godiva-style reason for it in this case and figured I'd respectfully extend the benefit of the doubt to two highly respected members of the community.


Scott

[RandyT]

I remember reading somewhere that MAME used Control, Alt, and Shift keys to work around the limitations of some keyboard encoders that would only register a certain number of keypresses since those three weren't included in the limitation.


By knowing that limitation/work around and looking at a keyboard, the MAME defaults make sense.

It was probably in one of my posts from not too long ago... 

I'm just asking about the logical/historic reasons, if any, behind I, K, J, and L being chosen as the P2B5-8 defaults for encoders.

If the answer is, "Andy pulled them out of thin air without considering 4-player panels and inertia has kept the settings that way," then that's the answer.

You keep referring to the choices for the defaults as "conflicts".  The has a negative connotation, and is an improper way of looking at things as it applies to this situation.

I can't tell you why Andy chose those defaults, only why I chose the ones I did for the KeyWiz.  There is a logical reason, and I gave it twice so far.   Once more for good measure...

No encoder is an X player specific encoder in the eyes of MAME or many other applications.  They are simply encoders, just as there are simply keyboards.  There is no hard and fast rule that states how any encoder must be used for any given panel.  It could be a two player panel with a joystick and 12 buttons per player, or a 4 player panel with a joystick and 4 buttons per player.  The number of inputs required are the same.  Using the P3 defaults for the P2 5-8 buttons on a two player panel, which MAME requires you to define anyway, makes no difference as there is no 3rd player in use, and those definitions are then already present for the 4-player configuration, should a builder decide to go that route.  There aren't enough inputs on a 32 or 40 input controller to accommodate the full gamut of the 4-player defaults, as this configuration necessarily dictates that inputs be borrowed from P1 and P2 in order to achieve it.  In the end, the goal is to support, by default, a configuration which fits the available inputs on an encoder extremely well, and then attempt to make alternative configurations as convenient as is possible.

No conflicts, just smart approaches to an equation with many variables.  It's not the simple answer you appear to be looking for, but it has been given.

[PL1]

You keep referring to the choices for the defaults as "conflicts".  The has a negative connotation, and is an improper way of looking at things as it applies to this situation.

OK, call it an "odd overlap" or "curious choice" if you prefer to avoid the negative connotation of "conflicts".


Scott

[PL1]

Answer cross-posted to this thread where the questions were originally asked.

Thanks again for shedding some light on this, Andy.   

MAME Player 2 Button 5-8 default keys are undefined and Player 3 directional default keys are I, K, J, and L.

Why do IPac2, IPac4, and KeyWiz use I, K, J, and L for Player 2 Button 5-8 default keys?   

Why does the IPac4 use I, K, J, and L for Player 2 Button 5-8 and Player 3 directional default keys? 

Thats a good question. I cant remember all the details but it was some time back in 2001, the I-PAC 2 came first and Mame did not have any keys assigned for player 2 SW 5-8. But I got those keys from somewhere, it was another emulator. I cant remember exactly which one, might have been Callus.

Then when the I-PAC 4 came out I had to assign the Mame defaults for player 3 and these overlapped unfortunately.

Scott