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Main => Driving & Racing Cabinets => Topic started by: Retro77 on February 10, 2021, 07:48:27 am

Title: Is there a workaround for MAME pot issue
Post by: Retro77 on February 10, 2021, 07:48:27 am

Hi all,

I wondered if anyone knew of a workaround when using GroovyMAME and setting pedals as buttons?

What I mean by this is, MAME will allow me to set the accelerator pot on for example, Special Criminal Investigation but when I press it in game it has no effect. I am guessing it is because there are several games that used switches instead of real potentiometers.

Is there a way around this? It would be a shame to have to remove some of these from the cab.

Thanks

Title: Re: Is there a workaround for MAME pot issue
Post by: PL1 on February 10, 2021, 11:55:11 am

Quote from: Retro77 on February 10, 2021, 07:48:27 am

I wondered if anyone knew of a workaround when using GroovyMAME and setting pedals as buttons?

What I mean by this is, MAME will allow me to set the accelerator pot on for example, Special Criminal Investigation but when I press it in game it has no effect. I am guessing it is because there are several games that used switches instead of real potentiometers.

Is there a way around this? It would be a shame to have to remove some of these from the cab.

MAME allows you to map an analog pedal axis to a button/microswitch pedal input.
- Highlight the input.
- Press ENTER.
- Press the pedal.

Just tried mapping an analog stick's Y-axis up to gas and Y-axis down to brake in SCI.
- Gas and brake worked perfectly during gameplay.
- The axis mapped whether it started in the center like an analog stick or at the end of the axis like an un-pressed pedal.
-- As long as MAME registers that the analog control moves far enough in a certain direction, it will map that direction to the input.

If your pedal maps to the input, that indicates that MAME sees it and that it should work during gameplay.   :dunno


Scott

Title: Re: Is there a workaround for MAME pot issue
Post by: Retro77 on February 10, 2021, 02:08:50 pm

Hi Scott,

Thanks for the response. I have just tried it again. I noticed that when I pressed a pedal on Gas Switch it mapped 2 controls.

Joy 2 Left Joy 2 Right

This works for the games that use potentiometers as far as I can tell so I assumed this was correct because for those games it just gets mapped as a Joy axis.

I am using an APAC. So I am thinking that maybe I have wired it incorrectly.

I deleted a control from each of the pedals on SCI.xml and now both pedals work. So I can roll out that fix to the other games.

Thanks again.

Title: Re: Is there a workaround for MAME pot issue
Post by: PL1 on February 10, 2021, 02:54:59 pm

Quote from: Retro77 on February 10, 2021, 02:08:50 pm

I noticed that when I pressed a pedal on Gas Switch it mapped 2 controls.

Joy 2 Left Joy 2 Right

Sounds like you quickly pressed and released the pedal.

If you press and hold the pedal for a few seconds, it should only map one direction.   ;D

Quote from: Retro77 on February 10, 2021, 02:08:50 pm

I am using an APAC. So I am thinking that maybe I have wired it incorrectly.

If the potentiometer center tab was wired wrong, you shouldn't get "Joy 2 Left" or "Joy 2 Right" mapped to an input.
- Check Windows Control Panel -- Devices and Printers -- right-click the game controller icon -- game controller settings -- properties to confirm that the pedal is working correctly.

Pretty sure that the only way your current setup could be mis-wired is if the axis moves in the opposite direction desired.
- If that is the case, swap the wires on potentiometer tabs 1 and 3 (5v and ground) or you can reverse the axis in the MAME "Analog Controls" menu.


Scott

Title: Re: Is there a workaround for MAME pot issue
Post by: Retro77 on February 10, 2021, 04:37:41 pm

Thanks for the tip. This is my first cab build, so assumed that was normal behaviour.

The pedals look to be working normally in Windows.