@psychosious You can also try to connect to 3.3 rail directly!
This might work for a status LED (on/off/error). If you want to use it for illumination effect the 3.3V can be a bit low.
Usually the forward current for blue LEDs are 2.9-3.1V
Keep in mind, the 3.3V rail delievers only 100mA!
That's enough for a few microcontrollers and a bunch of LEDs - not enough for your XMas tree!

@jkacza Sorry to say but i lost the scripts a while ago. Did a fresh install of RetroPie and forgot to back them up. Didnt bother to rewrite them as i moved the pi to a flirc case and there isnt much room and useful mounting points for a led.

But iirc the scripts were simple. Used this as a template:
https://raspi.tv/2013/how-to-use-soft-pwm-in-rpi-gpio-pt-2-led-dimming-and-motor-speed-control

Connected a RGB led to the gpio pins and wrote scripts for startup, game launch and game end.

I think the first step would be to test if I can capture audio natively before I pass it through to GPIO.

I've narrowed it down to wanting to use the alsa sound driver. I want to be able to hear the sound from my speakers while it's being captured which is looking like I'll need to use a loopback device. Eg snd-aloop

I'll update this post when I have more details but I've gotten so far as sorting dependencies and just need the proper configs for /etc/.asound.conf

It is important to note that the switch and the optional status LED need to be connected to the 2x2 pins header in any case. The signal break outs S1 and S2 are not meant for the switch and the LED, but rather for the communication between the PowerBlock and The RPi. Here is a summary for the connection between the break outs and the RPi:

S1: pin 12 S2: pin 11 5V OUT +: pin 2 or pin 4 5V OUT -: pin 6 or pin 9

@lurker It can be done. A lot of people jump to the direct GPU which cannot be done, however the Displayotron Hat LCD panels you can get for the Pi which run over the GPIO interface use a frambuffer which runs independently from the GPU, so terrible framerates overall but for displaying 2D graphics.static images it is perfectly acceptable. All you need is a display of similar construction with an SPI interface to send the image to.

@tropez You can't. It's the same on Xbox 360 controllers also. The lights indicating player number must be part of the proprietary drivers installed on each hardware system. The generic OS drivers used in Linux / RetroPie haven't included this function.

@petrockblog I think you can best answer on this ;)

I saw your switch built in a NESPi case - it should fit perfectly in.
But what will happen in the following scenarios:

I use a momentary switch and press the button to powerdown (I think it's clear what will happen) I use a momentary switch, do a shutdown via software (Quit >> Shutdown system)

The Mausberry switch fails in this case, because it will miss the physical button press and therefore needs a GPIO signal sended to the Mausberry circuit (Take a look here).

If you don't do this modification the Raspberry will shutdown as usual but the Mausberry switch is still active and does not respond to any button switch. So you have to cut main power or reset the circuit to make it work again.

Apologies @caver01 , electronics are a new experience for me :)

@ortsac I'm unsure (bought it as 'for spares or repair' from eBay) but presumably it's possible to change it?

@space-cadet So you soldered the LED directly onto the Mausberry circuit, rather than put it back to its original location? Thanks for letting me know, I wish the Mausberry website made that clear (!). I couldn't see any mention of de-soldering on their website.

@meleu said in Powering off via UI while using a Mausberry Circuit:

Do all the steps I showed on that topic and try to reboot your system. Describe here what happens.

And then perform this command: sudo systemctl disable killes; sudo systemctl stop killes and reboot your system. Describe here what happens.

SO, for starters, I have already done what you prescribed in the other thread to build the service and the killes.sh. Mine is till in the ~/bin folder, which is fine by me for now. After setting the killes.sh as executable, it works great! That is to say, I can do a software shutdown from command line for instance, and it definitely saves my metadata. Favorites and custom collections are awesome. Moreover, my additional line which triggers the NPN transistor does indeed let the Mausberry circuit know that a shutdown is imminent and it properly notices the drop on the GPIO it is monitoring and it cuts power. I really like this clever solution.

It also cuts power when I initiate a reboot. That makes sense to me, and for now I am willing to live with it. The point is that software shutdown requests properly exit ES and no longer lock up my Mausberry circuit.

Seems to me, the improvement to this would be to set a conditional statement before my GPIO command to trigger the transistor such that it checks to see if this is a shutdown/poweroff or if this is a reboot. I just don't know what to check to verify one way or the other--yet.

As for your command above, I initiated the command as you suggested and the system immediately did a shutdown, mausberry circuit powered off.

I solved the problem myself after doing alot of research. I found a 12 v power supply with a molex connector and a set of daisy chain wires that can power of molex and light the leds.

Yes, if the LED keeps on flashing the driver is not running properly.

Check out mausberry circuits. Very happy with mine

I can confirm that the information about the resistor is correct.

I placed my pi in an old SNES case. I wanted to get it as close to a real SNES as possible, so I've wired the original power and reset switches to the GPIO along with a small fan and thermostat which I've set to kick on if things get too hot. With the solution in this post I've also wired an LED to the GPIO. I currently have the LED hooked to the TX pin, but that was because it was supposed to kick on and off without any extra code. Since I had to use the solution in this post I suppose I may free up the serial port for some future enhancements.

Currently I am using CanaKit 5V 2.5a power supply which you can pick up for fairly cheap on Amazon. You would be hard pressed to push the pi beyond 2.5a.

This is exactly what I did. I used wire that was probably to thick so it seemed like an easier way to do it.