Blur Busters Forums

Who you gonna call? The Blur Busters! For Everything Better Than 60Hz™ Skip to content

[Mouse Mod HOWTO] Input lag test setup for Rocket League

Everything about input lag. Tips, testing methods, mouse lag, display lag, game engine lag, whole input lag chain, VSYNC OFF vs VSYNC ON, and more! Input Lag Articles on Blur Busters.

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby HalfwayDead » 20 Jul 2017, 05:18

Image
English isn't my mother tongue so I'm not sure what pin plunger means but I'm assuming it's the green one because that one is slightly different (square). When the button is pressed, all 3 pins have the same electric potential meaning the centre pin drops to 0V.
HalfwayDead
 
Posts: 20
Joined: 18 Jul 2017, 07:27

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby Sparky » 20 Jul 2017, 09:01

The little white button on the switches are called pin plungers. As opposed to lever or roller style microswitches.

Anyway, it looks like the green one is the common contact, the blue one may or may not be connected to anything.

As for finding that 3.3v rail, that 5 pin package designated U1 might be a voltage regulator. See if you can read the numbers off of it. Another good place to check is across those electrolytic capacitors.

Oh, and it's kind of hard to tell from the photo, but I think the thing you circled in red is a switch, no idea what it's for.
Sparky
 
Posts: 535
Joined: 15 Jan 2014, 02:29

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby HalfwayDead » 20 Jul 2017, 09:14

Sparky wrote:As for finding that 3.3v rail, that 5 pin package designated U1 might be a voltage regulator. See if you can read the numbers off of it. Another good place to check is across those electrolytic capacitors.

It says 38 S0E or maybe SOE if the font has a narrow O. The 38 is written together but there is a clear gap in the underlining.
HalfwayDead
 
Posts: 20
Joined: 18 Jul 2017, 07:27

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby Chief Blur Buster » 20 Jul 2017, 11:19

Good stuff!

Are you planning to use the mouse power supply, or the button cell power supply?

If I'm trying to save time while modifying a larger number of mouse quickly, this is what I prefer doing:

The quick more idiot-proof more accident-proof (button cell) technique is simply find two contacts that correspond to the mouse button. Once the multimeter leads are attached [solder bump, or button connector, or ribbon connector pin, etc] I then press (or short) the mouse button switch and watch the multimeter screen.

If using the coin battery plan, I don't even need to plug in the mouse (yet), or attach LED circuit (yet), to test for where I need to attach two wires. This is what makes the coin-battery technique so safe, easy, idiot-proof accident-proof when teaching an electronics newbie how to modify their mouse.

Once I find the two button attachments (usually at solder bumps underneath the button or pin connector) where voltmeter resistance that goes (near) 0 ohm when button pressed, (near) infinite-ohm when button released, that's where I attach two wires. Then reassemble the mouse.

That said, I usually plug in the disassembled mouse briefly anyway, to make sure that the switch I pressed, is actually the correct mouse button, and to determine the voltage polarities. And yes, to test LED before reassembling. But it is not necessarily mandatory to make the mouse live again until the wires are fully soldered and mouse reassembled, if you're very paranoid about plugging in a disassembled mouse. Voltage polarity can be tested after you finish modifying and reassembling the mouse, and safely attaching multimeter leads (in DC voltmeter mode) to the two wires coming out of an assembled mouse. This allows you to find out which polarity to safely attach the external button-cell-powered LED. (This avoids a lot of newbie mistakes: Accidental slips of blunt voltmeter leads on a cramped mouse motherboard, while the disassembled mouse is plugged into the computer, accidental shorts are common newbie-mistake when working with live electronics circuits). Even in the event of polarity mistake, the existence of LED -and- a resistor (yet another good reason to have a resistor, "just in case"), will keep accidental reverse polarity current low enough to not damage electronics. But you won't do that, because you'll multimeter-test a live reassembled mouse before attaching the LED circuit. ;)

That said, experienced electronics engineers will definitely strive to avoid the button cell, and do more testing/analysis necessary to fully bypass the need for the button cell.
(Literally 10x as much multimeter testing, depending on how complex the mouse is = lots more work when you're trying to mass-modify a large number of random discarded mice. When this is the goal, it is much faster and short-circuit safer, because of far less multimeter testing needed especially for clumsy hands)

Using the mouse's power supply to illuminate the LED, please keep corresponding here, so we can make sure you modify your circuit safely (good stuff, Sparky) -- Just adding further commentary to explain why the button-cell technique is useful for reduced risk/newbies/idiot-proofing/rapid random assembly purposes... Once done, take pictures of your final resulting circuit, so others will be able to take advantage of it for the same model mice.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter!
User avatar
Chief Blur Buster
Site Admin
 
Posts: 3668
Joined: 05 Dec 2013, 15:44

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby HalfwayDead » 20 Jul 2017, 11:48

Definitely button cell :D I'm no expert and as I said in my first post, the plan for the future is to test multiple controllers that I don't want to break.
From everything I tested so far the pins I marked blue and green have identical behaviour. I can send a mouse click with either of them. I guess I'll see once I have everything that I need.
HalfwayDead
 
Posts: 20
Joined: 18 Jul 2017, 07:27

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby Sparky » 20 Jul 2017, 19:10

HalfwayDead wrote:Definitely button cell :D

Then you don't need to worry about finding the voltage regulator. Good luck!
I'm no expert and as I said in my first post, the plan for the future is to test multiple controllers that I don't want to break.
From everything I tested so far the pins I marked blue and green have identical behaviour. I can send a mouse click with either of them. I guess I'll see once I have everything that I need.
Well, the green one is definitely connected to ground, so that it can pull the NO contact low. If blue is grounded while the button is pressed, then that's just tied to ground as well. I have strong opinions about that, but it's not really relevant to the test setup.
Sparky
 
Posts: 535
Joined: 15 Jan 2014, 02:29

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby HalfwayDead » 21 Jul 2017, 18:48

So I got the wiring and LEDs today. 1.6 V forward voltage which means 70 Ohms for 20 mA but I only got 10 Ohm and 100 Ohm so I tried 100 first because I was too lazy to put 7 resistors in a row. LED is already brighter than my monitor. Either way, I shouldn't have too much trouble recording it. My current settings are F2.8 Aperture, 1/1250 shutter speed and 800 ISO.

I have no experience with soldering so I'm gonna get my dad to help me. In the meantime I made a custom map and recorded a quick video as a proof of concept (no LED and handheld not even getting the whole screen, 1000 FPS in game) https://gfycat.com/ImpassionedBrilliantIbadanmalimbe. Interesting to see how much faster the monitor can transition to black than it can to white.

Thanks again for all the help. The method with the resistance worked great btw.
HalfwayDead
 
Posts: 20
Joined: 18 Jul 2017, 07:27

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby Chief Blur Buster » 21 Jul 2017, 21:39

HalfwayDead wrote:https://gfycat.com/ImpassionedBrilliantIbadanmalimbe. Interesting to see how much faster the monitor can transition to black than it can to white.

Yes, different colors can sometimes have different input lag -- because of slower GtG transitions for certain color pairs
GtG pixel response can vary from color to color, and that can mean different input lag for different colors. Fortunately, on high-Hz gaming monitors, the majority of GtG is complete within the first 1-2ms and you only need a few percent GtG to become initially human visible, anyway. For modern eSports TN monitors, GtG initation (first pixel movement) for all color pairs, occurs within 1ms, even if the GtG isn't complete for a long time after. So if you're high-speed-measuring modern well-overdriven TN panels at a 1000fps granularity to a 1ms error, asymmetric GtG lag isn't a noticeable distortion to results. However, GtG asymmetries are extremely huge on certain panels for certain color pairs (e.g. various dim greys to other dim greys on VA panels) -- certain color pairs sometimes adds several milliseconds of extra input lag compared to a simple black->white and white->black transition.

You don't get that with modern "1ms" TN. (Even if 1ms is only for GtG10%->90%). For all 256x256 (8-bit) transitions on good well-overdriven 1ms TN 144Hz+ monitors, all transitions have already begun emitting human-detectable photons in less than 1ms after beginning the GtG transition -- so input lag by color is quite consistent on modern 1ms TN 144Hz+ monitors nowadays (less than 1ms variance for "GtG transition to partial extent that is now sufficiently human visible" -- which can be even the first 10% of a pixel transition). Even if GtG will take 15-20ms to really fully completely do 100%, the human-visible partial GtG is already complete in the first 1ms for all possible color combinations on the majority of modern "1ms TN" gaming monitors. (Photodiode oscilloscope graphs will show the curve has already started shooting really fast within 1ms, even if not complete in 1ms).

But you're aiming for a 1ms error margin with a 1000fps camera, so GtG variances by color may not be meaningful on many high-end gaming monitors (<1ms variance in GtG-to-human-detect). So don't worry about input lag variances by color in most cases. Just something to keep in mind that it can emerge as measurable multi-millisecond factor (especially on 10-year-old LCD monitors, or on very specific color ranges on certain panel tech such as VA)

About resistor ohm value:
100 is probably fine. The safety margin with resistors + button cell is big. With the limitation of a button cell, it can be pretty much safely be off by an order of magnitude (50 ohm or 500 ohm) when just playing with LED+button cell because the button cell doesn't output enough power to blow up a typical red LED. I actually use 330 as my LEDs were plenty bright -- and I often used 2AA battery (3 volts) holders -- which output enough current to burn out some 1.6 volt red LED when used without a resistor. A bigger resistor value will simply dim the LED.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter!
User avatar
Chief Blur Buster
Site Admin
 
Posts: 3668
Joined: 05 Dec 2013, 15:44

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby HalfwayDead » 22 Jul 2017, 17:44

Image My current wiring. LED isolated at the top so I can get it close to the screen/on the screen. The blue and white cable are then going to get connected to the wires soldered to the mouse but for now I've got them connected to a different button. Battery is providing 3.3V right now and the LED is pretty bright. Still using the one 100 Ohm resistor.
HalfwayDead
 
Posts: 20
Joined: 18 Jul 2017, 07:27

Re: [Mouse Mod HOWTO] Input lag test setup for Rocket League

Postby Chief Blur Buster » 23 Jul 2017, 22:43

Thanks for posting your breadboard wiring diagram!

In 2013, we started out with something very roughly similar on a breadboard before later making a permanent soldered solution + MOLEX connectors. We used 330 ohm instead of 100 ohm, though.

If this is your first-ever time doing this stuff, now at least you've tested your circuit even before attaching the mouse. You may wish to add tape onto your coin battery to hold it down to breadboard, since you may jostle this breadboard around a bit more than expected during testing.

I see the button on the right is your temporary simulated mouse button.

For your breadboard it appears:
blue = you'll connect to negative (ground) of mouse button
white = you'll connect to positive of mouse button

It's also possible to test the LED circuit connected to the mouse before even plugging in the mouse to the computer.

Although steps can be merged by an experienced electronics hobbyist, the further "safe path" steps for those new to electronics are listed. Stop and go back a step (or few) to troubleshoot, if any steps isn't working.

1. Attach wires to mouse (preferably wires with connectors at end), if not done yet
Finding places to attach wires, can be tested-for and done without plugging in mouse. See earlier post described, you simply do continuity testing while testing the mouse buttons on an unplugged mouse. Basically the two solder joints on the mouse-motherboard closest to the mouse buttons or the mouse button connector.
2. Plug in mouse to computer
3. Verify mouse is still working with your wires attached (but without LED yet)
4. Test polarity with voltmeter on wires [+/- which way to connect wires]
5. Unplug mouse
6. Connect this breadboard to mouse wires with correct polarity. [common negative / common ground].
It may still work with swapped wires, but to be safe, let's not risk reverse current from coin battery flowing through mouse electronics
7. Test click [does LED light up?]
8. Plug in mouse to computer
9. Test move mouse without clicking [does mouse still work properly with circuit attached?]
10. If so, test click again [does LED still light up?]
11. Done.

Testing in this sequence, minimizes chance for accidental shorts/damage to a live mouse, especially if you've practically never done electronics before.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter!
User avatar
Chief Blur Buster
Site Admin
 
Posts: 3668
Joined: 05 Dec 2013, 15:44

PreviousNext

Return to Input Lag

Who is online

Users browsing this forum: No registered users and 1 guest