Pot values for yoke - hey Scott!

[Le Chuck]

Hey Scott, or anybody.  Let's talk pot values and yokes. 

I could google a lot of this but I'm not gonna.  I'm gonna post. 

If memory serves the original atari yokes used 10K pots. Incidentally I think a lot of other games used those too, some used 5K perhaps.  I think Tril used 10 but I can't remember.  Considering I used to own one I'm somewhat ashamed, but not very. 

Anyway, I'm 90% certain I have 10K pots in my yoke and my yoke interfaces through a KADE.  I notice that in some games I get nice smooth movement and others I'm moving in steps.  SW Trilogy is one of those, I move in steps rather than a nice smooth track and it makes me miss some shots.  A few MAME titles exhibit similar, even tho I've gone into mame and supermodel and adjusted the values for each. 

I'm wondering if this is a game thing or a hardware thing, or an emulator thing.  Would changing over to 100K pots help, in theory post calibration that would give ten times the steps for a game like Tril, if it is a emulator issue.  What says you all?

Solution:  Trilogy jitter was because my deadzone was set too low.  See a few posts down, or try 5% deadzone.   

[PL1]

If memory serves the original atari yokes used 10K pots. Incidentally I think a lot of other games used those too, some used 5K perhaps.

Most arcade analog controls I've researched use 5k pots but the resistance value isn't the main consideration UNLESS it is wired in a 2-wire (variable resistor) configuration.

As long as it is wired in a 3-wire (voltage divider/potentiometer) configuration, the important considerations are the taper ("linear 1" FTW), quality, and condition of the pot -- a dirty/rusty old Radio Shack el-cheapo is but a nice, long-life Allen Bradley or a Honeywell/Clarostat RV4 series is  .

I notice that in some games I get nice smooth movement and others I'm moving in steps.  SW Trilogy is one of those, I move in steps rather than a nice smooth track and it makes me miss some shots.  A few MAME titles exhibit similar, even tho I've gone into mame and supermodel and adjusted the values for each. 

I'm wondering if this is a game thing or a hardware thing, or an emulator thing.

If you're getting smooth motion in some games, the encoder probably isn't the problem unless there are more than 256 x 256 analog positions in the game.

IIRC Jon down-scaled the KADE's A/D conversion results from the 32u4's native 10-bit (1024) to 8-bit (256) position data to fit into the HID data-word size without adding another byte. (Apologies in advance if I messed up this description, Jon.  )

If the number of possible positions isn't causing the problem you are probably looking at either emulation limitations/errors or not enough computing horsepower.

Would changing over to 100K pots help, in theory post calibration that would give ten times the steps for a game like Tril, if it is a emulator issue.

Nope.  Remember that pots are analog, so there aren't 10x more "steps" in a 100k pot vs. a 10k.

The pot acts as a analog voltage divider and the encoder's A/D converter samples the analog voltage and converts it to to an 8-bit position. (~19.5 mV/step or 1.05 degrees/step)

If you need more steps, change the source code so your encoder outputs a 10-bit position. (~4.88 mV/step or 0.26 degrees/step)

Unless the wiper arm and/or resistive element of the pot are dirty/corroded/worn, changing pots will not help.


Scott

[Le Chuck]

Great reply Scott, ya know I knew most of that at some point, or was at least aware of it lol. 

Pots *should* be good but if I do decide to change them I'll go for decent ones of course.  We are wired up 3-wire, and I don't think it's a computing power issues either.  I need to dig into supermodel's settings and see what's going on, seems that's really the only game that's giving me fits.  Minor jitter in a few others, and I guess that Trilogy is minor too but I just care more about it lol. 

[processedmeat]

I need to dig into supermodel's settings and see what's going on, seems that's really the only game that's giving me fits.  Minor jitter in a few others, and I guess that Trilogy is minor too but I just care more about it lol.

In SW trilogy, I get the occasional twitch where the cursor jumps way to the left every so often.  The funny thing is that I had to basically set the deadzone to zero in order to reduce this glitch. 

Here's part of my .ini that has to deal with the analog controls.  Can you post yours?  Am I missing anything else that could affect this?

Code: [Select]

InputJoy1XOffVal = -739
InputJoy1XMaxVal = 32411
InputJoy1XDeadZone = 0
InputJoy1YMinVal = 32010
InputJoy1YOffVal = 4516
InputJoy1YMaxVal = -32306
InputJoy1YDeadZone = 1
Thanks

[Le Chuck]

I need to dig into supermodel's settings and see what's going on, seems that's really the only game that's giving me fits.  Minor jitter in a few others, and I guess that Trilogy is minor too but I just care more about it lol.

In SW trilogy, I get the occasional twitch where the cursor jumps way to the left every so often.  The funny thing is that I had to basically set the deadzone to zero in order to reduce this glitch. 

Here's part of my .ini that has to deal with the analog controls.  Can you post yours?  Am I missing anything else that could affect this?

Code: [Select]

InputJoy1XOffVal = -739
InputJoy1XMaxVal = 32411
InputJoy1XDeadZone = 0
InputJoy1YMinVal = 32010
InputJoy1YOffVal = 4516
InputJoy1YMaxVal = -32306
InputJoy1YDeadZone = 1
Thanks

What encoder are you using and do you get similar behavior if you go to the windows joy config utility and play around the test screen?  Jumps like that are usually the game getting a bad signal.  You didn't post your InputJoy1XMinVal, if it isn't in the neighborhood of -28k to -33k that could account for the jumps.  Are they always in the same direction? 

So I figured out my issue, I had my deadzone set at 1%.  This caused all that jitter, it wasn't epileptic or anything but it made a difference.  Here's what I did.  Went into the game and played Yavin twice.  Both times I died at least once on the first scene and second scene but was able to clear the third on a life. 

Went into supermodel -config-inputs and recalibrated.  Minor difference in values, in the neighborhood, and noticed that the calibration utility was setting my deadzone at 1%.  That seemed really tight so I played Yavin and had similar results.  Made a copy of the ini and manually set deadzone to 5%, cleared Yavin no loss of life (Vader got away tho).  Set deadzone to 7% and started dying again, so it looks like I just needed to manually dial in my deadzone.  My current values are below.  Can't believe I went how long (years) and never screwed with the config utility deadzone values.  Mostly because I'm an idiot...and it wasn't that bad.  It was like a little jitter, but enough to make a pretty decent gameplay difference.  Now those crosshairs move nice and smooth.

Code: [Select]

InputJoy1XMinVal = -31906
InputJoy1XOffVal = -862
InputJoy1XMaxVal = 31586
InputJoy1XDeadZone = 5
InputJoy1YMinVal = 29520
InputJoy1YOffVal = -762
InputJoy1YMaxVal = -32768
InputJoy1YDeadZone = 5
     

Of course, I still suck a big fat one in all the special light saber scenes because the Y axis gets flipped and so all of the sudden trying to hit those diagonal shots and cross screen swipes is like doing split second rocket surgery underwater and I eat it...every damn time.

[processedmeat]

What encoder are you using and do you get similar behavior if you go to the windows joy config utility and play around the test screen?  Jumps like that are usually the game getting a bad signal.  You didn't post your InputJoy1XMinVal, if it isn't in the neighborhood of -28k to -33k that could account for the jumps.  Are they always in the same direction? 

I'm using the A-Pac.  Funny thing is when I went to config the inputs it records everything except for the InputJoy1XMinVal.  I edited my config.ini and set it for something in the -32K range but I still get the occasional glitch.  In the USB controller configuration, the cursor doesn't jitter nor show the glitch.  Really weird.

On a side note, do you have the InputAnalogJoyTrigger2 activated in your config.ini file to do the rapid fire in Trilogy?  Supposedly, if you alternate the triggers then it fires faster.   I tried setting it up in mine but for some reason it doesn't enable that button.  It makes it hard to complete the game since I can't rapid fire. 

[wp34]

CossackWarrior on KLOV is selling NOS 5k Pots.

https://forums.arcade-museum.com/showthread.php?t=394791

[Le Chuck]

CossackWarrior on KLOV is selling NOS 5k Pots.

https://forums.arcade-museum.com/showthread.php?t=394791

Awesomesauce

I just might have $40 burning a hole in my pocket...

I'm using the A-Pac.  Funny thing is when I went to config the inputs it records everything except for the InputJoy1XMinVal.  I edited my config.ini and set it for something in the -32K range but I still get the occasional glitch.  In the USB controller configuration, the cursor doesn't jitter nor show the glitch.  Really weird.

On a side note, do you have the InputAnalogJoyTrigger2 activated in your config.ini file to do the rapid fire in Trilogy?  Supposedly, if you alternate the triggers then it fires faster.   I tried setting it up in mine but for some reason it doesn't enable that button.  It makes it hard to complete the game since I can't rapid fire. 

I've owned that game and never knew about rapid fire lol.  I just would hammer on that trigger as fast as I could lol.  I don't, I have them both mapped to the same, but I'll go set it up and see how it does. 

If the A-Pac isn't registering the min val then it'll be hard to say where the jitter is coming from.  I know it's a PITA but if it does bother you might be worth changing over to a KADE or control pad hack. 

[Le Chuck]

On a side note, do you have the InputAnalogJoyTrigger2 activated in your config.ini file to do the rapid fire in Trilogy?  Supposedly, if you alternate the triggers then it fires faster.   I tried setting it up in mine but for some reason it doesn't enable that button.  It makes it hard to complete the game since I can't rapid fire.

My version of supermodel is so old it doesn't even have the second trigger enabled in the emulator lol.  Spent part of today updating that...and I've got Lost World running on the cab so yay, kids'll like that!  Off screen reloading via a button is a PITA but they'll learn, or die.  Once I find a newer build of supermodel that will work on tinyXP I'll let you know what I discover. 

[processedmeat]

I ended up redoing the Supermodel control calibration and noticed that there was a number after "joy" that indicates which controller I was using.

So it should have been InputAnalogJoy1Trigger2 instead of InputAnalogJoyTrigger2 in my config.ini file.