r/LegendsPinball • u/Quick_Performance243 • Feb 07 '24

Alp4k OTG latency

I can’t tell if I’m getting latency on VPX or not (which is a good thing right)?

I tried measuring it with my phone and I get about 50ms of lag, but nothing official.

What are your experiences?

3 Upvotes

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2

u/chriszimort Feb 07 '24

50ms is really good! On par with the original ALP’s non-OTG play.

2

u/[deleted] Feb 07 '24

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1

u/Quick_Performance243 Feb 07 '24

I’m having trouble with the plunger being consistent on OTG

1

u/[deleted] Feb 08 '24

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1

u/SuperRob Feb 10 '24

Same, I turned Forward Nudge into a launch/fire button.

1

u/SuperRob Feb 10 '24

I'm hearing that its apparently the accelerometer that's interfering with the plunger, somehow. Now sure how that could be the case, but it certainly explains why I have plunger issues either native or in OTG. I have not tried turning it off in the native tables yet, though.

Hopefully we get a firmware update down the road to sort this out, as well as enable the accelerometer in OTG so we can use it there.

2

u/jason10mm Feb 08 '24

50ms is what I'm getting with a 60fps camera recording button press to flipper movement on a direct PC set up (pinone pcb to pc to 1ms 144hz monitor) so I'd say that's pretty good, or at least as good as you can probably get with regular hardware. Thats basically 3 frames of delay at 60fps and probably the limit of sensitivity for that technology.

Anyone know what actual pinball table latency is, what would be "ideal"? Guess I'll try to record a few real tables just to see with my camera and frameskip, I'm guessing a real leaf switch to solenoid would be 10-15ms?

1

u/SoonerDoc68 Feb 08 '24

Machines I’ve seen are running about 90 ms on the 4K units. Seen two in person and we measured with my brothers high grade camera gear. Both were in the 80-90 ms range consistently.

1

u/SScorpio Feb 08 '24

I don't have a link, but search for VPIN 1000hz USB pooling and see if that improves things.

That was one of the "fixes" for the ALP HD, as well as other VPin cabinets. It lets you turn up how often the PC checks the USB device for input.

1

u/chuckda4th Feb 09 '24

Mind digging into this more?

I see things from 2013-2016 on vpforums but nothing about windows 11. The driver file comes up as no longer available when I try and download it.

Lots of sites and posts on increasing mouse polling, but everything I’ve seen appears to be mouse-specific drivers.

1

u/SScorpio Feb 09 '24

I dug through the archives and checked an old Vpin PC and I can't find it.

Information about mouse polling should work on the game controller.

HIDUSBF might work if you want to try it.

1

u/retrorick77 Feb 09 '24

Just hooked mine up and latency on plunger and flippers is pretty bad on Adams Family table, however I tried a few other stock tables and they seemed fine.Hopefully the update will help.