Hackvision video game system

Hackvision is the tiny, hackable, Arduino-based video game system. Available in mid-October with a retail price of under $40 USD.
UPDATE: Hackvision is now available! Learn all the details!

Features:

• NO Arduino is required. Based on Arduino technology so you can write your own games and upload them using the Arduino IDE. All you need is a USB-Serial cable or adapter like this or this.
• Connects directly to your TV with standard RCA connections. One for audio, one for video. Works with NTSC or PAL (Europe, Africa, Asia, South America) TVs.
• Integrated button controller right on the PCB.
• Preloaded with awesome Space Invaders and Pong games. More games coming. You can write them, too.
• Other controllers supported: Wii nunchuk, SuperNES, or paddle controllers you can make from a potentiometer and button.
• Software libraries for game development and controller support.
• High score files stored in EEPROM so they are retained even with power off.
• All unused pins broken out to pads for your hacking pleasure!
• Non-conductive adhesive foam pad protects the bottom of the board from your fingers.
• All through-hole components. Kit can be assembled in 30-60 min. Fully assembled and tested units will also be available.
• Additional accessories will be available for purchase including 9V adapters, RCA cables, Wii nunchuk breakout boards, paddle controller kits, USB-Serial adapters, etc.

Could this be the perfect gift for the 2010 holiday season? (yes)

Here’s a preview of the Space Invaders game. I let the title sequence run before I started playing:

Distributors may email sales@nootropicdesign.com for distributor pricing.

It's tiny!

Difficulty Level = 3 [What’s this?]

The MQ-3 is an alcohol gas sensor that is available for about $5 from Sparkfun, Seeed Studio, and others. It’s easy to use and has sparked the imagination of anyone who has dreamed of building their own breathalyzer device for measuring the amount of alcohol in the human body. I got an MQ-3 sensor a couple of months ago and have spent a lot of time trying to figure out how to do this. After lots of “data gathering”, I found that this task is not as easy as it sounds.

MQ-3 Alcohol Sensor

First of all, don’t try to use the MQ-3 as a way to determine if you are sober enough to drive. If you’ve been drinking, just don’t drive! And if you’ve had a few drinks, don’t do any soldering either.

read more…

Toolduino is an open-source software tool that you use to test your Arduino circuits. Toolduino communicates with your Arduino through a serial connection so that you can manipulate the pin outputs and read the inputs. Go to the Toolduino page to download it and for all the details on how to use it!

Difficulty Level = 1 [What’s this?]

Most keypads like this are wired so it makes it straightforward to figure out what button is being pressed. With 3 columns and 4 rows of buttons, you only need 7 wires. Typically all the buttons in a column are connected together with the same wire, and all the buttons in a row are connected together with the same wire. To determine which button is pressed, you apply a voltage to the wire attached to a column and then check the wires attached to each row to see if current is flowing through any of them. If so, then the switch for a particular button is closed (button pressed). Then you proceed to the next column and try each row again, etc. Not rocket science — just scanning a bunch of switches to see which one is closed. In fact, there is a keypad library in the Arduino Playground that makes it easy to do this.

Well, the keypad I bought here has 10 wires instead of 7, and it’s wired in a really goofy way. I’m not sure if this is common, but I thought keypads were generally wired as described above. Here’s the schematic that shows how this one is actually wired:

Schematic of my non-standard keypad

Notice that the gray wire is used only for the 9 key. And the orange wire is only used for the * key. And the brown wire is only used for the # key. Why is this built so inefficiently? I have no idea!

Regardless, here is Arduino code that I used to scan this keypad. You can do something similar if you have a keypad that is not wired in a straightforward way.

// Pins
#define BLACK 2
#define WHITE 3
#define GRAY 4
#define PURPLE 5
#define BLUE 6
#define GREEN 7
#define YELLOW 8
#define ORANGE 9
#define RED 10
#define BROWN 11

#define STAR 10
#define POUND 11


void setup() {
  Serial.begin(115200);

  // Rows
  pinMode(BLACK, INPUT);
  digitalWrite(BLACK, HIGH);  // set pull-up resistors for all inputs

  pinMode(WHITE, INPUT);
  digitalWrite(WHITE, HIGH);

  pinMode(GRAY, INPUT);
  digitalWrite(GRAY, HIGH);

  pinMode(PURPLE, INPUT);
  digitalWrite(PURPLE, HIGH);

  pinMode(ORANGE, INPUT);
  digitalWrite(ORANGE, HIGH);

  pinMode(BROWN, INPUT);
  digitalWrite(BROWN, HIGH);


  // Columns
  pinMode(BLUE, OUTPUT);
  digitalWrite(BLUE, HIGH);

  pinMode(GREEN, OUTPUT);
  digitalWrite(GREEN, HIGH);

  pinMode(YELLOW, OUTPUT);
  digitalWrite(YELLOW, HIGH);

  pinMode(RED, OUTPUT);
  digitalWrite(RED, HIGH);

}

void loop() {
  int key = scanKeypad();

  if (key != -1) {
    if (key == STAR) {
      Serial.println("*");
    } else {
      if (key == POUND) {
        Serial.println("#");
      } else {
          Serial.println(key);
      }
    }
  }
}

int scanKeypad() {
  int key = -1;

  // Pull the first column low, then check each of the rows to see if a
  // button is pressed.
  digitalWrite(BLUE, LOW);
  if (digitalRead(BLACK) == LOW) {
    key = 1;
  }
  if (digitalRead(WHITE) == LOW) {
    key = 4;
  }
  if (digitalRead(PURPLE) == LOW) {
    key = 7;
  }
  digitalWrite(BLUE, HIGH);

  // Moving on to the second column....
  digitalWrite(GREEN, LOW);
  if (digitalRead(BLACK) == LOW) {
    key = 2;
  }
  if (digitalRead(WHITE) == LOW) {
    key = 5;
  }
  if (digitalRead(PURPLE) == LOW) {
    key = 8;
  }
  digitalWrite(GREEN, HIGH);

  // Third "column".  Note that the 0 key is wired to this column even though
  // the 0 is really in the second column.
  digitalWrite(YELLOW, LOW);
  if (digitalRead(BLACK) == LOW) {
    key = 3;
  }
  if (digitalRead(WHITE) == LOW) {
    key = 6;
  }
  if (digitalRead(GRAY) == LOW) {
    key = 9;
  }
  if (digitalRead(PURPLE) == LOW) {
    key = 0;
  }
  digitalWrite(YELLOW, HIGH);

  // Last "column" is not really it's own column.  Only wired to * and #
  digitalWrite(RED, LOW);
  if (digitalRead(ORANGE) == LOW) {
    key = STAR;
  }
  if (digitalRead(BROWN) == LOW) {
    key = POUND;
  }
  digitalWrite(RED, HIGH);

  return key;
}