[GUIDE] Wiring Diagrams: all-in-one board, graceful shutdowns, audio-only board

[PotaTox]

If you do that the headphones would be mono right and mono left. I think it also works after the amp.

It's kind of ambiguous because all the examples I found mention using line level (pre-amplified) audio. But at the same time, I did not find anything that said "Don't use a summing circuit on amplified audio or else you'll break stuff". I'll probably try it both ways and see what happens. I have an extra speaker at least.

I used two 1k resistors to combine the amplified output and it was really soft. The smallest resistor I could find in my spare part box was 100 ohm and the volume was usable, but still noticeably softer than a straight single channel. The pot and emulationstation are at max volume. I may just go back to a mono speaker and use headphones if there is a game where stereo sound actually makes a difference in playability, we'll see..

Why do we need resistors? Can you try it just combining the two outputs with a wire?

[a3k4]

It's kind of ambiguous because all the examples I found mention using line level (pre-amplified) audio. But at the same time, I did not find anything that said "Don't use a summing circuit on amplified audio or else you'll break stuff". I'll probably try it both ways and see what happens. I have an extra speaker at least.

I used two 1k resistors to combine the amplified output and it was really soft. The smallest resistor I could find in my spare part box was 100 ohm and the volume was usable, but still noticeably softer than a straight single channel. The pot and emulationstation are at max volume. I may just go back to a mono speaker and use headphones if there is a game where stereo sound actually makes a difference in playability, we'll see..

Why do we need resistors? Can you try it just combining the two outputs with a wire?

You need to lower the output using resistors otherwise the audio will sound garbled.

[PotaTox]

I used two 1k resistors to combine the amplified output and it was really soft. The smallest resistor I could find in my spare part box was 100 ohm and the volume was usable, but still noticeably softer than a straight single channel. The pot and emulationstation are at max volume. I may just go back to a mono speaker and use headphones if there is a game where stereo sound actually makes a difference in playability, we'll see..

Why do we need resistors? Can you try it just combining the two outputs with a wire?

You need to lower the output using resistors otherwise the audio will sound garbled.

Garbled because it's too loud? Then you could just turn the volume down.

[voldemortvdk]

Please guide me how to wire Arduino Pro Micro (for replacing Teensy) to the RPi.
Teensy board, there are GND / Vcc / D+ / D- pins, but Arduino Pro Micro are Vcc/Tx/Rx/GND, the micro-usb on it too small for soldering wire )

Thank you

[a3k4]

Please guide me how to wire Arduino Pro Micro (for replacing Teensy) to the RPi.
Teensy board, there are GND / Vcc / D+ / D- pins, but Arduino Pro Micro are Vcc/Tx/Rx/GND, the micro-usb on it too small for soldering wire )

Thank you

You might want to ask in this thread

[jazzy]

Hi all,

Just recieved the all in one board and decided to test a simple circuit, usb power to Rpi-0, then Rpi-0 connected to screen. Then wires from Rpi-0 usb and power from jumpers on the back of the pi to the usb "to rasberry pi" holes on the all in one board. I've connected up the 4 face buttons, start select and the dpad. So far im not getting any usb input, and the board is v 1.4. Is there a way to test the signals from the board are getting picked up from the pi through command line or some other way?

Thanks

[EDIT] False alarm, i wired a usb connector to a usb hub, so i could access the menus via a keybaord, The all in one board picked up automatically as a USB game pad, managed to rebind keys. Amazing device truly plug and play

[musty_666]

Hi, I have two questions

What is the utility for Polulu slide switch?

And, what's the code to program the GPIO pins? The audio code is uploaded by wermy, but, how can I program the other pins?

Sorry for my english.

[a3k4]

Hi, I have two questions

What is the utility for Polulu slide switch?

And, what's the code to program the GPIO pins? The audio code is uploaded by wermy, but, how can I program the other pins?

Sorry for my english.

This post will answer both of your questions. The Polulu is for a graceful shutdown; however @Popcorn is now suggesting using @Camble's method instead - I will update the diagrams at some point to reflect this. Please see Popcorn's post or Github for code details.

[warrell]

Im using Helders audio board and have followed the Standard wiring diagram (v2.5) to wire the teensy. This is of course different to Wermys set up so the Arduino Project he wrote won't work. I have amended it but its not working for me ill post the code below can anyone take a look and advise please.

Code: Select all

#include <Bounce.h>

#define NUM_KEYS 12

struct Key {
  char keycode;
  Bounce* bounce;
};

Key keys[NUM_KEYS];

Key key(char keycode, int pin) {
  Key *ret = new Key;
  ret->keycode = keycode;
  ret->bounce = new Bounce(pin, 10);
  pinMode(pin, INPUT_PULLUP);
  return *ret;
}

void setupKeys() {
  keys[0] = key('w', 14);
  keys[1] = key('s', 15);
  keys[2] = key('a', 16);
  keys[3] = key('d', 17);
  keys[4] = key('p', 18);
  keys[5] = key('l', 19);
  keys[6] = key('o', 20);
  keys[7] = key('k', 21);
  keys[8] = key('x', 22);
  keys[9] = key('z', 23);
  keys[10] = key('q',24);
  keys[10] = key('e',25);
}

void setup() {
  setupKeys();
  Keyboard.begin();
  //  pinMode(0, INPUT_PULLUP);
}

void loop() {
  for (int i = 0; i < NUM_KEYS; i++) {
    keys[i].bounce->update();
    if (keys[i].bounce->fallingEdge()) {
      Keyboard.press(keys[i].keycode);
    } else if (keys[i].bounce->risingEdge()) {
      Keyboard.release(keys[i].keycode);
    }
  }
}

[a3k4]

Im using Helders audio board and have followed the Standard wiring diagram (v2.5) to wire the teensy. This is of course different to Wermys set up so the Arduino Project he wrote won't work. I have amended it but its not working for me ill post the code below can anyone take a look and advise please.

Code: Select all

#include <Bounce.h>

#define NUM_KEYS 12

struct Key {
  char keycode;
  Bounce* bounce;
};

Key keys[NUM_KEYS];

Key key(char keycode, int pin) {
  Key *ret = new Key;
  ret->keycode = keycode;
  ret->bounce = new Bounce(pin, 10);
  pinMode(pin, INPUT_PULLUP);
  return *ret;
}

void setupKeys() {
  keys[0] = key('w', 14);
  keys[1] = key('s', 15);
  keys[2] = key('a', 16);
  keys[3] = key('d', 17);
  keys[4] = key('p', 18);
  keys[5] = key('l', 19);
  keys[6] = key('o', 20);
  keys[7] = key('k', 21);
  keys[8] = key('x', 22);
  keys[9] = key('z', 23);
  keys[10] = key('q',24);
  keys[10] = key('e',25);
}

void setup() {
  setupKeys();
  Keyboard.begin();
  //  pinMode(0, INPUT_PULLUP);
}

void loop() {
  for (int i = 0; i < NUM_KEYS; i++) {
    keys[i].bounce->update();
    if (keys[i].bounce->fallingEdge()) {
      Keyboard.press(keys[i].keycode);
    } else if (keys[i].bounce->risingEdge()) {
      Keyboard.release(keys[i].keycode);
    }
  }
}

I haven't delved into the code yet, maybe @Helder or @hueblo can help?