Skeleton Attiny85 Handheld

done! :)

I bought a bunch of things as a result of the feedback in the video comments and what people said before that already - basically a whole set for casting stuff in resin. Then I designed a case mould in 123D Design where I would cast the negative silicone mould in. The silicone came out wonderfully, but when I tried to pre-seal the switch and IC socket, the resin got into the parts, meaning I have to resolder them. It also seems as if the ratio wasn't mixed 100% right, as the resin is still very liquid, although it has been poured 3-4 hours ago. If it is not hard tomorrow morning, then I will mix up a new batch and remove the first layer of resin to start over. 

So I made a revision of this project for my first episode for element14 :)  

At one point I had a thought that I could vary the time between asking the charlieplexed buttons and add a piezo buzzer to one pin to get some noises out of the little handheld. But then you would have to have sound all the time, because you want to scan the buttons as well.

It would make much more sense to have the buttons connected via a bunch of resistors to the ADC, so you get free pins and a way to add a buzzer. The project I named in an earlier log is a way better basis to do so. 

It was fun to solder up the prototype and build a charlieplexed "keyboard" for the first time, but programming a game for it wasn't really on the time table sadly. I enjoyed the positive feedback from everyone on social media though and might think of something at a later point. Thanks for having this contest, hackaday people!

Hehe... just noticed the countdown said "since" and not "until". Anyways, nice to add some thoughts afterwards then!

I admit it was a bit trial and error development, but it worked out in the end.

#define pin_1 1
#define pin_2 4
#define pin_3 3

#define B_UP 0
#define B_DN 1
#define B_LF 2
#define B_RT 3
#define B_A 4
#define B_B 5

boolean pinChanged = false;
uint8_t pinstate = 0;
uint8_t pins[3] = { pin_1, pin_2, pin_3 };
uint8_t switches[6][2] =
{
  { pin_2, pin_1 },
  { pin_1, pin_3 },
  { pin_3, pin_1 },
  { pin_1, pin_2 },
  { pin_3, pin_2 },
  { pin_2, pin_3 }
};



void setup()
{
}

void loop()
{
  if (pinChanged)
  {
    pinChanged = false;
    if (pinstate & (1 << B_UP))
    { 
    }

    if (pinstate & (1 << B_DN))
    {
    }
    
    if (pinstate & (1 << B_LF))
    {
    }
    
    if (pinstate & (1 << B_RT))
    {
    }
    
    if (pinstate & (1 << B_A))
    {
    }
    
    if (pinstate & (1 << B_B))
    {
    }
  }

  for (uint8_t i = 0; i < 6; i++)
  {
    deactivate_all();

    // set pin states for button
    pinMode(switches[i][0], INPUT_PULLUP);
    pinMode(switches[i][1], OUTPUT);
    digitalWrite(switches[i][1], LOW);


    if (pinstate & (1 << i))
    {
      if (digitalRead(switches[i][0]) == HIGH)
      {
        pinstate &= ~(1 << i);
        pinChanged = true;
      }
    }
    else
    {
      if (digitalRead(switches[i][0]) == LOW)
      {
        pinstate |= (1 << i);
        pinChanged = true;
      }
    }
  }
}

void deactivate_all()
{
  for (uint8_t i = 0; i < 3; i++)
  {
    pinMode(pins[i], OUTPUT);
    digitalWrite(pins[i], HIGH);
  }
}

You need this to make the Arduino IDE be able to flash ATTINY based boards

https://raw.githubusercontent.com/damellis/attiny/ide-1.6.x-boards-manager/package_damellis_attiny_index.json

And this worked for me when trying to make the OLED run

https://www.instructables.com/id/ATTiny85-connects-to-I2C-OLED-display-Great-Things/

nice start so far :) I will try to port the games from @Daniel Champagne for the #Tiny Joypad by @megazoid to this handheld, because I made the buttons work yesterday! With a trick I might be able to add some sound, but not like them. I really enjoy their take on the attiny85 handheld and the 3D printed case with a swappable / rotating display.

The broken OLED is replaced, I've added some more of the threads that I made stronger with the help of liquid super glue! The tweet that I almost deleted because I feared spamming people got pretty crazy in comparison of my usual tweets.

https://twitter.com/davedarko/status/1072076882957484033