I’ve read all of the posts and seen all the diagrams, and as of now have every other button soldered and wired besides the trigger buttons (LT and RT). I am using an official Microsoft XBox 360 controller and want to make sure that what I am about to solder is accurate.
Looking at the three solder points for the RT trigger, as shown below in a quick Photoshop mock up I made, Would this be the correct way to enable LT and RT?
Thanks for posting this thread, I wanted to ask the same thing, I couldn’t discern the complete set of info from the other trigger thread. Apparently there are two different kind of Madcatz common ground pcbs and one of harder to hack the RT/LT?
I have a 4716 from 2007 (late version on slagcoin), which method of wiring the triggers should I go with? Is the OP’s method correct?
put one 10k Ohm resistor between the middle and bottom holes i believe. then wire to the signal / ground lines and it’ll work just fine. did this the other day actually on an OEM 360 controller.
cool that you made a pic like that, i too hacked a 360 pad recently the uncommon ground btw so i searched the whole padhacking thread but couldnt find an accurate explaining and just tried a couple of combinations till it worked…
i havent done it that way though, i used only 1 resistor for each trigger…
dont have the pad right now with me but i ll take a pic or make one if you people want
also i havent tried it on a 360 yet just on PC and it works OK
On the official controllers, only one resistor is needed per trigger, between the high and wiper points, which are the lowest two points on both sides. You then run a button to the top point and center point to activate it. I don’t believe you can use the common that the digital buttons use, pretty sure it’s not actually true ground.
Using this picture as a guide, I ran some tests through the pc joypad config window. Running a resistor from the mid to low points, I then did the following:
Running a signal from the top point to mid point (without ground):
[INDENT]Result: The Z-Axis appears to be altered to a minimum state, but no buttons. (Is this the desired effect??)
Running a ground/signal combo to the mid point: Result: Error that restarts the joypad
[/INDENT]
This would support my personal findings posted above. I’m new to circuit board work and the fact that a signal from the top to mid points works without a ground confused me. Am I right to assume that on pc’s the triggers will be listed as Axis effects rather than button changes? My educated guess would say yes since before removing the triggers they are analog by design.
I have a feeling that as long as it supports analog function, it won’t use the basic grounding functions because its more of a “slider” of electrical flow then an on/off configuration.
But as all things in life go, I could be so horribly wrong that people end up dying for it.
For third party controllers, it gets more complicated. Some are set up the same way as the official controller, and only require one resistor per trigger. Others, like the recent madcatz, are inverted, and require 2 resistors and an NPN transistor per trigger. The easiest way to test is to measure the voltage of the middle pin, using the ground from the usb, when controller is on and the trigger isn’t pressed. If the trigger reads as grounded while unpressed, it needs the transistor setup. If it reads as having a voltage, 3.3v or so I believe, it’s the same as the official controller and can use just a single resistor per trigger.
Do you have any good reading material for learning such intricacies? At this point I could probably hack most devices that use a simple ground/signal setup… but I wouldn’t mind learning the details.
bakageta, thank you for explaining that. i have a 2008 madcatz pad with the potentiometers still attached… i can’t tell if the trigger is in the on or off position, because the trigger assembly basically fell apart when i removed the case. what i did was to turn each trigger until each wiper read zero volts, and then hot glued them in place.
since i am now having problems with the ‘X’ button now, i am considering giving at least one of these triggers a go.
just one more question - you said that if the trigger is off and you read zero volts from the wiper then it needs the advanced setup… so are you saying that it is impossible to get zero volts from the middle wiper on the MS official pads, regardless of the position of the potentiometer?
Hi.
I actually did some testing on the oem controller yesterday.
What i find is that the ground for the trigger pot is not the same as the common signal ground for the rest of the controller. If you messure between the low side of the pot to the signal ground iyou see that it is not connected.
It is however grounded with the voltage ground from the USB cable, so i guess they seperated power ground and signal common ground on this pad for some reason.
For the fun of it I wanted to test if it is possible to connect the two ground layers together (to eliminate multiple ground straps out to buttons.), my findings is that this is not possible. The pad will not power up…
Conclusion:
We have to live with the fact that the LT/RT buttons has to be groundet from the power ground in the pad.
And to end all discussions with how to wire these buttons:
when you look at the boart from the trigger potmeter side.
1- GND
2- Slider
3- V high
You mount a 5-10k Ohm resistor between 2 and 3. This is a pullup resistor.
You connect your button between 1 and 2. The button will pull the high signal to ground and activate the switch. This will not make a ground short because of the big pullup resistor.
You can use the same ground wire to daisychain to both your switches.
It’s definitely possible to get 0v on the official pads, but that’s when the button is pressed. The older MadCatz were the same way, which means you have one of the new ones if setting both to 0v doesn’t register as holding both triggers down always. The easiest way to see if the trigger is off or on is to plug it into your pc, go to the controller properties, and move the potentiometer to see what counts as fully pressed and fully released, then measure the voltage when you know what state it’s in. The “complicated” setup for the new madcatz really isn’t that hard though, I’m sure you’ll be fine.
That’s actually conveniently mapped out on the slagcoin diagrams… It’s why LT/RT are a different color than all of the digital buttons, and the digital buttons all go to a red Common point instead of the pink Ground. Though, now that I think about it there is at least one of the slagcoin diagrams that has them labeled wrong, listing the LT/RT ground as common, and the common for the digital buttons as ground, but they are still listed separately.
The reason they don’t have the ground from pin 1 is they probably just used ground from another location. On the Madcatz, I believe the common ground controllers all actually use a true ground for the digital buttons as well, which means the triggers can use the same ground chain as your other buttons, unlike the official controllers.
Keep in mind that there are two versions of the “late” 4716, and if you recently picked up a new one, it’s probably got the harder to hack triggers rather than the easier ones like in the picture you linked. The newer ones have the trigger signal inverted, which means you need to use a transistor setup so they can use the same ground as the rest of the controller.
It’s why LT/RT are a different color than all of the digital buttons, and the digital buttons all go to a red Common point instead of the pink Ground. Though, now that I think about it there is at least one of the slagcoin diagrams that has them labeled wrong, listing the LT/RT ground as common, and the common for the digital buttons as ground, but they are still listed separately.