Published February 14, 2023 © MIT

Candy Box Gameboy

The ATTBOY is a very basic Attiny85-based game console that is housed in a candy box and runs the space invaders game.

BeginnerFull instructions provided1 hour580

Things used in this project

Hardware components

Microchip ATtiny85

Arduino Nano R3

PCBWay Custom PCB

Story

Hi everyone! Welcome back

So here's something extremely cool and intriguing: a tiny Gameboy that fits inside a Candy Tin box and runs doom, no, not really.

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This project is essentially an Altoid game console, however, it comes in a box made by a different candy company and has a different shape than a typical Altoid tin.

Altoid game consoles, also known as "Altoid tin game consoles, " are a unique type of custom game console that has become popular among DIY enthusiasts and gamers.

The concept is simple: take an Altoid tin, a small, pocket-sized mint container, and transform it into a functioning handheld game console. The tin is retrofitted with components such as a microcontroller, buttons, and a screen to create a compact and portable gaming device.

This game system only supports one game, a space invaders-style game. An SSD1306 display is used, while the console's ATTINY85 MCU serves as its brain.

A small 50mm × 50mm PCB that contains the entire project is crammed inside the Candy Box.

In this article, we will explore the process of creating a small, custom game console that you can call your own. Whether you're a seasoned electronics enthusiast or a beginner looking for a new project, this article will guide you through the steps of designing and building a compact and portable gaming device.

Material Required

These are the materials used in this built-

Custom PCB
Attiny85
Arduino Nano (for programming the Attiny85)
SMD Buttons
10k Resistors
1k Resistor
USB Micro THT Port
SSD1306 OLED Display
DIP8 Socket
M7 Diode
PCB Standoff M3
Screws M3
Altoid-like Candy Tin

Design

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The Candy Tin Box that I purchased from a neighborhood market served as the inspiration for this project's design.

The plan was to use a square box and install a PCB that houses all the electronics inside.

Originally, I planned to create a device similar to the Nintendo Gameboy Advance SP that folds into a little box, with the display on top and the controls on the bottom.

This concept was interesting but difficult to implement, so I set it aside for later and created a single PCB that will house the Attiony85 on the back side and the display on the top side, along with all the SMD components.

Preparing the Box

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We begin by first preparing the box for the Gameboy conversion, which includes making two mounting holes with a sharp punching tool. Although we can use a drill here, I found that the tin was too thin, so the punching tool did the job for me.

Then, using two M3 screws, we secure the two Hex M3 PCB standoffs over the holes so that the PCB can be attached to them.

We measure the distance between two hex PCB standoffs from their centers. This measurement, coupled with the inner length and breadth, which were approximately 51x51mm, will be used in the PCB design process.

PCB Design

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When it comes to PCB design, I used a design that was adapted from Electronoob's game console project, which you can find here.

https://electronoobs.com/eng_arduino_tut120.php

Here, an SSD1306 OLED Display is connected to an Attiny85 through the D3 and D4 pins.

There are three buttons: the Left and Right arrows are controlled by two of them, while the fire button is operated by the third.

A USB port that is also connected to a battery powers the entire system (in this article, we only utilize USB power; the battery isn't used, but it is available as a port for connecting a battery on board).

Using the measurements from before, I prepared the board, finished the schematic, and then arranged each component according to its proper location.

The Gerber data for this board was later sent to PCBWAY for samples.

PCBWAY

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After completing the PCB Design, Gerber data was generated and sent to PCBWAY for samples.

An order was placed for the PCBs with white soldermask and black silkscreen, which look pretty cool in general.

I received PCBs within a week, and they were excellent, as expected.

I love the quality of PCBs made by PCBWAY. There are other manufacturers available, but their service is always on another level.

check out PCBWay service for getting great PCB service at less cost.

Solderpaste Dispensing and Pick & Place Process

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Using a solderpaste dispensing system, we initially begin the PCB assembly by applying solder paste one by one to each component pad.
Using an ESD Tweezer, we then select and position each component in its designated location.

Hotplate Reflow

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Next, we carefully lifted the whole circuit board and place it on my DIY Mini Hotplate which is also homemade just like this project.

After a little time, when the hotplate reaches the temperature where the solder paste is melting, all of the components will be soldered using this hot reflow process.

THT Process

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The DIP8 IC socket and USB Micro Port are the final THT components that are assembled after the Reflow Process.
We next secure them in place by soldering their pads.

Adding PCB Standoffs to Board

After removing the PCB standoffs from the tin and adding them to the PCB, we proceed to add them to the circuit.

This is why: There are screw holes in the center of the circuit, but they are concealed by the SSD1306 Display. If a display is added, it also hides the screw head, making it impossible to tighten the screws with a screwdriver.

Therefore, we add the display to its position after first tightening the PCB standoffs.

Adding OLED Display

The OLED display is then put in its place, its leads are soldered from the bottom, and the leads are then chopped down using a wire cutter. The circuit assembly is now finished.

Result so far

Here is the result so far, and the board doesn't look awful. The visual impact of this board is increased by the addition of graphics to the silkscreen layer of the PCB.

Let's look at the programming portion of this project since assembly is complete but the console's brain has not yet been installed in its IC socket.

Programming Attiny85

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Now here's one of the best examples of how a simple 1$ Chip can run stuff like an Arduino board without using a bunch of componenets and other stuff.

Attiny85 is by far one of the best MCU I used, it's not because of its connectivity or features like BT or wifi (It doesn't have those).

It's a low-power Microchip 8-bit AVR® RISC-based microcontroller that combines 8 KB ISP Flash memory, 512B EEPROM, 512B SRAM, six general-purpose I/O lines, 32 general purpose working registers, one 8-bit timer/counter with compare modes, one 8-bit high-speed timer/counter, USI, internal and external Interrupts, 4-channel 10-bit A/D converter, programmable watchdog timer with internal oscillator, three software selectable power saving modes, and debugWIRE for on-chip debugging. The device achieves a throughput of 20 MIPS at 20 MHz and operates between 2.7-and 5.5 volts.

Attiny85 is great because of how well it can do certain things that an Arduino can perform as well but in a smaller much more user-friendly form factor. we can implement it into any kind of project and it will work smoothly.

I've been using it for the past 5 years and I will still use it in the future because of its reliability and the most important factor- cost!.

*datasheet for attiny85*

As for the Flashing Process, we cannot directly program ATTINY85 through any USB, I mean there's a method for programming the Attiny straight from the USB port but I'm not doing that.

Instead, I'll be using the ISP flashing method which will utilize the SPI Pins of attiny85 to burn the bootloader in it and then Flash.

We go to Example sketches> Arduino as ISP and upload it into the Arduino Nano board.
Next, we add a 1uf Capacitor between RST and GND Pin, this will stop Arduino to reset during the flashing process (Add capacitor after uploading the Arduino as ISP Sketch)
Now go to this link and download the Attiny85 Core files-

https://github.com/SpenceKonde/ATTinyCore

Next, we wire Attiny85's SPI Pins with Arduino Pins according to the attached wiring diagram.
we then go to tools and change the MCU and choose Attiny85.
We select the right port and change the programmer to "Arduino as ISP"
Next, we click on Burn Bootloader, if the wiring is correct, you will see a "Done burning Bootloader" message.
At Last, we go to the sketch menu and select "upload using programmer" and the board will get flashed with the sketch which was opened at that moment.

For flashing the MCU, I used my existing AVR Flasher which Is an Arduino Nano that runs Arduino as an ISP sketch.

The Attiny85 MCU is simply inserted into the DIP8 Socket, burned with code, and then removed and connected to the Main Circuit's DIP8 Socket.

Adding and removing the Attiny85 is not practical and could result in breaking or bending its legs, but there is a way we can change that, perhaps in the next version. This process is similar to adding old-school game cartridges to game consoles. The only difference is that the old cartridges were big and much more practical.

GAME

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The Attiny85 is added to the DIP8 Socket, and a 5V source is connected to the gaming console via the USB Micro Port.

Both Space Invaders and the Board appear to be functioning well.

As the net that connects one end of the switch to D5 was not connected in the design, I had to manually adjust the board and add a shorting wire.

Let's proceed to the last step, which is the box construction, now that this works.

Final Assembly

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Using a cutter and nose pliers, we first begin by removing a part of the tin box's front face to make space for a USB port.
Following that, we secure the circuit with two M3 bolts inside the tin box.

Assembly is now completed.

END RESULT

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Here is the finished product of this build: a small, portable game system that plays a bootleg version of Space Invaders using components jammed within a tin box. It functions and is exactly what it says it is.

This is it for today, Leave a comment if you guys need any help, and I'll be back with another project soon!

Thanks, PCBWAY for supporting this project, Do check PCBWAY for getting great PCB service for less cost!

Peace

Code

#include <EEPROM.h>
#include "font6x8AJ.h"
#include <avr/sleep.h>
#include <avr/interrupt.h> // needed for the additional interrupt

#define DIGITAL_WRITE_HIGH(PORT) PORTB |= (1 << PORT)
#define DIGITAL_WRITE_LOW(PORT) PORTB &= ~(1 << PORT)

// Routines to set and clear bits (used in the sleep code)
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))

// Defines for OLED output
#define SSD1306XLED_H
#define SSD1306_SCL   PORTB4  // SCL, Pin 4 on SSD1306 Board - for webbogles board
#define SSD1306_SDA   PORTB3  // SDA, Pin 3 on SSD1306 Board - for webbogles board
#define SSD1306_SA    0x78  // Slave address

// Function prototypes
void resetAliens(void);
void drawPlatform(void);
void sendBlock(int);
void playSpaceAttack(void);
void beep(int,int);
void levelUp(int);
void drawFire(int x, int y);
void doDrawLS(long, byte);
void doDrawRS(long, byte);
void clearAlienArea(int row, int lastActive);
void doNumber (int x, int y, int value);
void ssd1306_init(void);
void ssd1306_xfer_start(void);
void ssd1306_xfer_stop(void);
void ssd1306_send_byte(uint8_t byte);
void ssd1306_send_command(uint8_t command);
void ssd1306_send_data_start(void);
void ssd1306_send_data_stop(void);
void ssd1306_setpos(uint8_t x, uint8_t y);
void ssd1306_fillscreen(uint8_t fill_Data);
void ssd1306_char_f6x8(uint8_t x, uint8_t y, const char ch[]);
void ssd1306_draw_bmp(uint8_t x0, uint8_t y0, uint8_t x1, uint8_t y1, uint8_t bitmap[]);

long firecounter = 0; // Timer for managing fire
long aliencounter = 0; // Timer for alien movement
int mothercounter = 0; // Timer for movement of the mothership
int level = 1; // Game level - incremented every time you clear the screen
int mothershipX = 0; // position of mothership
int mothership = 0; // is mothership active?
int mothershipWidth = 8; // mothership width in pixels
int fireXidx, fireYidx; // mapping of player fire locaiton onto array of aliens
int leftLimit; // furtherst left in x-axis pixels that the aliens are currently
int positionNow = 0; // current position of the alien array (as steps from the left)
boolean alienDirection = 1; // current direction of travel for alien swarm - 1 is right 0 is left
int alienRow = 0; // which alien row are we considering
int alienFire[5][3]; // max 5 lots of alien fire  - indices are active, xpos, ypos
int playerFire[3]; // one lot of player fire - indices are active, xpos, ypos
boolean row[4][10]; // on-off array of aliens
int firstAlien = 0; // index of first live alien in the array
int lastAlien = 8; // index of last live alien in the array
int newFirst = firstAlien; // as above when it changes
int newLast = lastAlien; // ...
int aliensDead = 0; // how many aliens have been killed in total on this level?
int lastActiveRow = 2; // what's the lowest row in which we will find live aliens?
int deadOn1 = 0; // how many aliens are dead on row one (middle row)
int deadOn2 = 0; // how many aliens are dead on row two (bottom row)

boolean fire = 0;
int topScoreB = 0;
int player; //0 to 128-platformWidth  - this is the position of the player
int platformWidth = 16; 
boolean stopAnimate = 0; // this is set to 1 when a collision is detected
boolean mute = 0;
boolean newHigh = 0;
int score = 0; // score - this affects the difficulty of the game
int top = 0;

// Interrupt handlers
ISR(PCINT0_vect){ // PB0 pin button interrupt           
   if (digitalRead(2)==1) fire = 1;
}

void playerIncSpaceAttack(){ // PB2 pin button interrupt
  if (digitalRead(0)==1) fire = 1;
}

// Arduino stuff - setup
void setup() {
  DDRB = 0b00000010;    // set PB1 as output (for the speaker)
  PCMSK = 0b00000001; // pin change mask: listen to portb bit 1
  GIMSK |= 0b00100000;  // enable PCINT interrupt 
  sei();          // enable all interrupts
}

// Arduino stuff - loop
void loop() { 
  ssd1306_init();
  ssd1306_fillscreen(0x00);
  
  // The lower case character set is seriously compromised because I've had to truncate the ASCII table
  // to release space for executable code - hence lower case y and w are remapped to h and / respectively.
  // There is no z in the table (or h!) as these aren't used anywhere in the text here and most of the 
  // symbols are also missing for the same reason (see my hacked version of font6x8.h - font6x8AJ.h for more detail)
  ssd1306_char_f6x8(0, 1, "A L I E N");
  ssd1306_char_f6x8(4, 2, "A T T A C K");
  ssd1306_char_f6x8(0, 4, "by A R N O V"); // see comments above !

  ssd1306_setpos(85,1);
  ssd1306_send_data_start();
  sendBlock(1);
  sendBlock(0);  
  sendBlock(1);
  ssd1306_send_data_stop();
  ssd1306_setpos(85,2);
  ssd1306_send_data_start();
  sendBlock(0);
  sendBlock(2);
  sendBlock(0);
  ssd1306_send_data_stop();
  ssd1306_setpos(85,3);
  ssd1306_send_data_start();
  sendBlock(0);
  sendBlock(0);  
  sendBlock(1);
  sendBlock(0);  
  sendBlock(1);
  ssd1306_send_data_stop();
  player = 96;
  drawPlatform();

  long startT = millis();
  long nowT =0;
  boolean sChange = 0;
  while(digitalRead(0) == HIGH) {
    nowT = millis();
    if (nowT - startT > 2000) {
      sChange = 1;     
      if (digitalRead(2) == HIGH) {
        EEPROM.write(0,0);
        EEPROM.write(1,0);
        ssd1306_char_f6x8(8, 0, "-HIGH SCORE RESET-");  
      } else if (mute == 0) { mute = 1; ssd1306_char_f6x8(32, 0, "-- MUTE --"); } else { mute = 0; ssd1306_char_f6x8(23, 0, "-- SOUND ON --");  }    
      break;
    }
    if (sChange == 1) break;
  }  
  while(digitalRead(0) == HIGH);


  if (sChange == 0) {
    for (byte mm = 112;mm>=1;mm--) {
      if ( (mm>=32) && (mm<56) ) drawFire(104,mm);
      if (mm == 32) {
        ssd1306_setpos(100,3);      
        ssd1306_send_data_start();
        sendBlock(0);
        ssd1306_send_data_stop();
        ssd1306_setpos(100,4);      
        ssd1306_send_data_start();
        sendBlock(0);
        ssd1306_send_data_stop();
        beep(30,100);
      }
      ssd1306_setpos(mm,0);      
      ssd1306_send_data_start();
      sendBlock(3);
      sendBlock(0);
      ssd1306_send_data_stop();
      drawPlatform();
      delay(20);
    }
    ssd1306_setpos(0,0);      
    ssd1306_send_data_start();
    sendBlock(0);
    sendBlock(0);
    ssd1306_send_data_stop();
    ssd1306_char_f6x8(0, 6, "R E T R O");  // see comments above !
    ssd1306_char_f6x8(0, 7, "/GAME CONSOLE");  // see comments above !
    delay(1500);
    ssd1306_init();
    ssd1306_fillscreen(0x00);
    stopAnimate = 0;
    score = 0;

    playSpaceAttack(); 
    top=topScoreB;
    
    ssd1306_fillscreen(0x00);
    ssd1306_char_f6x8(11, 1, "----------------");
    ssd1306_char_f6x8(11, 2, "G A M E  O V E R");
    ssd1306_char_f6x8(11, 3, "----------------");
    ssd1306_char_f6x8(37, 5, "SCORE:");
    doNumber(75, 5, score);
    if (!newHigh) {
      ssd1306_char_f6x8(21, 7, "HIGH SCORE:");
      doNumber(88, 7, top);
    }
    for (int i = 0; i<1000; i = i+ 50){
      beep(50,i);
    }
    delay(2000);
    if (newHigh) {
      ssd1306_fillscreen(0x00);
      ssd1306_char_f6x8(10, 1, "----------------");
      ssd1306_char_f6x8(10, 3, " NEW HIGH SCORE ");
      ssd1306_char_f6x8(10, 7, "----------------");
      doNumber(50,5,top);
      for (int i = 700; i>200; i = i - 50){
      beep(30,i);
      }
      newHigh = 0;
      delay(2700);    
    } 
  }
  system_sleep();
}

void doNumber (int x, int y, int value) {
    char temp[10] = {0,0,0,0,0,0,0,0,0,0};
    itoa(value,temp,10);
    ssd1306_char_f6x8(x, y, temp);
}

void ssd1306_init(void){
  DDRB |= (1 << SSD1306_SDA); // Set port as output
  DDRB |= (1 << SSD1306_SCL); // Set port as output

  ssd1306_send_command(0xAE); // display off
  ssd1306_send_command(0x00); // Set Memory Addressing Mode
  ssd1306_send_command(0x10); // 00,Horizontal Addressing Mode;01,Vertical Addressing Mode;10,Page Addressing Mode (RESET);11,Invalid
  ssd1306_send_command(0x40); // Set Page Start Address for Page Addressing Mode,0-7
  ssd1306_send_command(0x81); // Set COM Output Scan Direction
  ssd1306_send_command(0xCF); // ---set low column address
  ssd1306_send_command(0xA1); // ---set high column address
  ssd1306_send_command(0xC8); // --set start line address
  ssd1306_send_command(0xA6); // --set contrast control register
  ssd1306_send_command(0xA8);
  ssd1306_send_command(0x3F); // --set segment re-map 0 to 127
  ssd1306_send_command(0xD3); // --set normal display
  ssd1306_send_command(0x00); // --set multiplex ratio(1 to 64)
  ssd1306_send_command(0xD5); // 
  ssd1306_send_command(0x80); // 0xa4,Output follows RAM content;0xa5,Output ignores RAM content
  ssd1306_send_command(0xD9); // -set display offset
  ssd1306_send_command(0xF1); // -not offset
  ssd1306_send_command(0xDA); // --set display clock divide ratio/oscillator frequency
  ssd1306_send_command(0x12); // --set divide ratio
  ssd1306_send_command(0xDB); // --set pre-charge period
  ssd1306_send_command(0x40); // 
  ssd1306_send_command(0x20); // --set com pins hardware configuration
  ssd1306_send_command(0x02);
  ssd1306_send_command(0x8D); // --set vcomh
  ssd1306_send_command(0x14); // 0x20,0.77xVcc
  ssd1306_send_command(0xA4); // --set DC-DC enable
  ssd1306_send_command(0xA6); // 
  ssd1306_send_command(0xAF); // --turn on oled panel 
}

void ssd1306_xfer_start(void){
  DIGITAL_WRITE_HIGH(SSD1306_SCL);  // Set to HIGH
  DIGITAL_WRITE_HIGH(SSD1306_SDA);  // Set to HIGH
  DIGITAL_WRITE_LOW(SSD1306_SDA);   // Set to LOW
  DIGITAL_WRITE_LOW(SSD1306_SCL);   // Set to LOW
}

void ssd1306_xfer_stop(void){
  DIGITAL_WRITE_LOW(SSD1306_SCL);   // Set to LOW
  DIGITAL_WRITE_LOW(SSD1306_SDA);   // Set to LOW
  DIGITAL_WRITE_HIGH(SSD1306_SCL);  // Set to HIGH
  DIGITAL_WRITE_HIGH(SSD1306_SDA);  // Set to HIGH
}

void ssd1306_send_byte(uint8_t byte){
  uint8_t i;
  for(i=0; i<8; i++)
  {
    if((byte << i) & 0x80)
      DIGITAL_WRITE_HIGH(SSD1306_SDA);
    else
      DIGITAL_WRITE_LOW(SSD1306_SDA);
    
    DIGITAL_WRITE_HIGH(SSD1306_SCL);
    DIGITAL_WRITE_LOW(SSD1306_SCL);
  }
  DIGITAL_WRITE_HIGH(SSD1306_SDA);
  DIGITAL_WRITE_HIGH(SSD1306_SCL);
  DIGITAL_WRITE_LOW(SSD1306_SCL);
}

void ssd1306_send_command(uint8_t command){
  ssd1306_xfer_start();
  ssd1306_send_byte(SSD1306_SA);  // Slave address, SA0=0
  ssd1306_send_byte(0x00);  // write command
  ssd1306_send_byte(command);
  ssd1306_xfer_stop();
}

void ssd1306_send_data_start(void){
  ssd1306_xfer_start();
  ssd1306_send_byte(SSD1306_SA);
  ssd1306_send_byte(0x40);  //write data
}

void ssd1306_send_data_stop(void){
  ssd1306_xfer_stop();
}

void ssd1306_setpos(uint8_t x, uint8_t y)
{
  if (y>7) return;
  ssd1306_xfer_start();
  ssd1306_send_byte(SSD1306_SA);  //Slave address,SA0=0
  ssd1306_send_byte(0x00);  //write command

  ssd1306_send_byte(0xb0+y);
  ssd1306_send_byte(((x&0xf0)>>4)|0x10); // |0x10
  ssd1306_send_byte((x&0x0f)|0x01); // |0x01

  ssd1306_xfer_stop();
}

void ssd1306_fillscreen(uint8_t fill_Data){
  uint8_t m,n;
  for(m=0;m<8;m++)
  {
    ssd1306_send_command(0xb0+m); //page0-page1
    ssd1306_send_command(0x00);   //low column start address
    ssd1306_send_command(0x10);   //high column start address
    ssd1306_send_data_start();
    for(n=0;n<128;n++)
    {
      ssd1306_send_byte(fill_Data);
    }
    ssd1306_send_data_stop();
  }
}

void ssd1306_char_f6x8(uint8_t x, uint8_t y, const char ch[]){
  uint8_t c,i,j=0;
  while(ch[j] != '\0')
  {
    c = ch[j] - 32;
    if (c >0) c = c - 12;
    if (c >15) c = c - 6;
    if (c>40) c=c-9;
    if(x>126)
    {
      x=0;
      y++;
    }
    ssd1306_setpos(x,y);
    ssd1306_send_data_start();
    for(i=0;i<6;i++)
    {
      ssd1306_send_byte(pgm_read_byte(&ssd1306xled_font6x8[c*6+i]));
    }
    ssd1306_send_data_stop();
    x += 6;
    j++;
  }
}

void system_sleep() {
  ssd1306_fillscreen(0x00);
  ssd1306_send_command(0xAE);
  cbi(ADCSRA,ADEN);                    // switch Analog to Digitalconverter OFF
  set_sleep_mode(SLEEP_MODE_PWR_DOWN); // sleep mode is set here
  sleep_enable();
  sleep_mode();                        // System actually sleeps here
  sleep_disable();                     // System continues execution here when watchdog timed out 
  sbi(ADCSRA,ADEN);                    // switch Analog to Digitalconverter ON  
  ssd1306_send_command(0xAF);
}

void beep(int bCount,int bDelay){
  if (mute) return;
  for (int i = 0; i<=bCount; i++){digitalWrite(1,HIGH);for(int i2=0; i2<bDelay; i2++){__asm__("nop\n\t");}digitalWrite(1,LOW);for(int i2=0; i2<bDelay; i2++){__asm__("nop\n\t");}}
}



/* ------------------------
 *  SpaceAttack Code
 */
void playSpaceAttack() {

  firecounter = 0; // Timer for managing fire
  level = 1; // Game level - incremented every time you clear the screen
  topScoreB = 0; // highscore
  score = 0; // obvious
  
  // Initialisations
  for (byte i = 0; i<5;i++) {
    alienFire[i][0] = 0;
  }
  resetAliens();

  levelUp(1); // This also does various essential initialisations
  
  attachInterrupt(0,playerIncSpaceAttack,CHANGE);

  while (stopAnimate == 0) {
    while(1) {
    aliencounter++;
    firecounter++;
    mothercounter++;
    
    // deal with inputs
    if(analogRead(0) < 940) fire =1; // this reads the reset pin (pin 1) of the Attiny85 - to use it, see comments section above

    if(digitalRead(2)==1) {
      if (digitalRead(0)==1) fire = 1;
      if(player < 127-platformWidth) {
        player++;
        } 
    }
    if (digitalRead(0)==1){
      if (digitalRead(2)==1) fire = 1;
      if (player >1){
        player--;
        } 
     }

    if ( (mothership == 0) && (random(0,1000) > 998) && (alienRow>0) ) {
      mothership = 1;
      mothershipX= 127-16;
    }

    // draw aliens
    for (int inc = 0; inc <= lastActiveRow; inc ++) {
      ssd1306_setpos((positionNow*8),inc+alienRow);
      ssd1306_send_data_start();
      for (int bl = firstAlien; bl <=lastAlien; bl++){
        if(row[inc][bl]==1){
          if (inc == lastActiveRow) {
            if(random(0,1000) > (999-level)) { // this alien is going to fire!
              byte afIndex = 0;
              while (alienFire[afIndex][0] == 1) {
                afIndex++; // search for empty alien fire option
                if (afIndex == 5) break;
              } 
              if (afIndex < 5) { // we've found a slot
                alienFire[afIndex][0] = 1; // activate fire on this slot
                alienFire[afIndex][1] = ( (positionNow*8) + ((bl-firstAlien) * 8) + 4); // x position
                alienFire[afIndex][2] = (inc+alienRow+1)*8; // Where the fire starts
              }
            } // end of this alien firing
          } // only if we are on the lowest row of live aliens
          if ( (inc == 0) || (inc == 2) ) {
            sendBlock(1);
          } else {
            sendBlock(2);
          }
        }else {
          sendBlock(0);
        }
       }   
      ssd1306_send_data_stop();
    }


    // Display the score
    doNumber(0,6,score);
    
    // Burn clock cycles to keep game at constant (ish) speed when there are low numbers of live aliens 
    int burnLimit = (8-(lastAlien-firstAlien));
    for (int burn = 0; burn < burnLimit; burn+=2) {                  
        drawPlatform();    
        }

    // Display the mothership
    if (mothercounter >= 3) {
      mothercounter = 0;    
      // draw mothership
      if (mothership) {
        ssd1306_setpos(mothershipX,0);
        ssd1306_send_data_start();
        sendBlock(3);
        sendBlock(0);
        ssd1306_send_data_stop();
        mothershipX --;
        if (mothershipX == 0) {
          mothership = 0;                      
          ssd1306_setpos(mothershipX,0);
          ssd1306_send_data_start();
          sendBlock(0);
          sendBlock(0);
          ssd1306_send_data_stop();
        }
      }
    }

    // Move the aliens
    if (aliencounter >= (92-((level-1)*5)) ) {
        aliencounter = 0;
      if(alienDirection) { // Moving right
        // move down a row
        if (positionNow >= 6+(8-(lastAlien-firstAlien))) {
          alienDirection = 0;
          clearAlienArea(alienRow,lastActiveRow);                                   
          alienRow++;
        } else {
          positionNow++;
        }
      } else { // Moving left
        // move down a row
        if (positionNow <= 0) {
          alienDirection = 1;
          clearAlienArea(alienRow,lastActiveRow);                                   
          alienRow++;
        } else {
          positionNow --;
        }
      } 
      clearAlienArea(alienRow,lastActiveRow);                                   
    }

    // Fire !
    if ((fire == 1) && (playerFire[0] == 0)) { // fire has been pressed and we're not currently firing - initiate fire!!
      playerFire[0] = 1;
      playerFire[1] = player+platformWidth/2; // xposition of new fire!
      playerFire[2] = 56;
    }

    // Handle all firing-related stuff (in both directions!)
    if (firecounter >= 2) {                  
      firecounter = 0;
      // --- Deal with player Firing --- 
      if (playerFire[0] == 1) {                      
          drawFire(playerFire[1], playerFire[2]);
          if (playerFire[2] == 0) {
            ssd1306_setpos(playerFire[1],0);
            uint8_t temp = B00000000;
            ssd1306_send_data_start();
            ssd1306_send_byte(temp);  
            ssd1306_send_data_stop();                                                          
            playerFire[0] = 0;
            fire = 0;
          } else {
            playerFire[2] = playerFire[2] - 1;                          
          }
      }
      
      // aliens are at positionNow * 8 + 8* their index
      
      leftLimit = positionNow*8;
      if ((fire == 1)) {
        fireXidx = firstAlien + floor((playerFire[1]-positionNow*8)/8);                    
        fireYidx=  floor(floor(playerFire[2]/8) - alienRow);
        
        if((mothership == 1) && (playerFire[1] >= mothershipX) && (playerFire[1] <= mothershipX +8) && playerFire[2] <=8) {
          long scm = random(1,100);
          if (scm<30) {
            score +=50;
          } else if (scm<60) {
            score += 100;
          } else if (scm<90) {
            score += 150;
          } else {
            score += 300;
          }
            
          beep(30,400);
          beep(30,300);          
          beep(30,200);
          beep(30,100);
          mothership = 0;
          ssd1306_setpos(mothershipX,0);
          ssd1306_send_data_start();
          sendBlock(0);
          sendBlock(0);
          ssd1306_send_data_stop();
        }

        // Alien has been hit
        if ((playerFire[1] >= leftLimit) && (fireYidx>=0) && (fireYidx<=lastActiveRow) && (fireXidx>=0) && (fireXidx<9)) {                    
          if (row[fireYidx][fireXidx] == 1) { 

            int lastActiveToClear = lastActiveRow; // if we kill the last alien on a row - we still need to clear that row (end of this fn)
            
            if (fireYidx == 2) deadOn2++;
            if (fireYidx == 1) deadOn1++;
            
            if (deadOn2 == 5) {lastActiveRow = 1;}
            if ((deadOn1 == 4) && (deadOn2 == 5)) {lastActiveRow = 0;}

            score = score + (int)((3-fireYidx) * 10);
                        
            aliensDead++;                      
            ssd1306_setpos(playerFire[1],alienRow+fireYidx+1);
            uint8_t temp = B00000000;
            ssd1306_send_data_start();
            ssd1306_send_byte(temp);  
            ssd1306_send_data_stop();                                                          
            beep(30,100);
            
            fire = 0;
            playerFire[0] = 0;
            playerFire[1] = 0;
            playerFire[2] = 7;
            row[fireYidx][fireXidx] = 0;
            
            if (fireXidx == firstAlien) { // this is the first Alien - sweep back and reset to new first alien
              for (int xi = lastAlien; xi>=firstAlien;xi--) {
                if ( (row[0][xi] == 1) || (row[1][xi] == 1) || (row[2][xi] == 1) ) newFirst = xi;
              }
              positionNow += newFirst - firstAlien;
              firstAlien = newFirst;
            }
            
            if (fireXidx == lastAlien) { // this is the last Alien - sweep thru and reset to new last alien
              for (int xi = firstAlien; xi<=lastAlien;xi++) {
                if ( (row[0][xi] == 1) || (row[1][xi] == 1) || (row[2][xi] == 1) ) newLast = xi;
              }
              lastAlien = newLast;
            }
            clearAlienArea(alienRow,lastActiveToClear);
                                               
          }         
        }
      }


      // --- Deal with Alien Firing --- 
      for (byte afIndex = 0; afIndex<5; afIndex++) {
        if(alienFire[afIndex][0] == 1) {
          drawFire(alienFire[afIndex][1],alienFire[afIndex][2]);
          alienFire[afIndex][2] = alienFire[afIndex][2] + 1;

          if (alienFire[afIndex][2] >= 56) {
            ssd1306_setpos(alienFire[afIndex][1],7);
            uint8_t temp = B00000000;
            ssd1306_send_data_start();
            ssd1306_send_byte(temp);  
            ssd1306_send_data_stop();                                                          
            alienFire[afIndex][0] = 0; // the fire's got to the end
            if( ((alienFire[afIndex][1]) > player) && ( (alienFire[afIndex][1]) < player+platformWidth) ) { // you've been hit!!
              stopAnimate = 1;
              goto die;
              }
          }
        }                  
      } // end of aliens firing                  
    }

    if (aliensDead == 14) {
      for (int ai = 0; ai <= 5; ai++) alienFire[ai][0] = 0;

      level++;
      if (level>15) level = 15;
      levelUp(level);

      resetAliens();
    }
    
    if( ((alienRow == 5) && (lastActiveRow == 2))||  ( (alienRow == 6) && (lastActiveRow == 1)) || ((alienRow == 7) && (lastActiveRow == 0)) || stopAnimate) {
      stopAnimate = 1;
      break;
    }
    // draw the player
    drawPlatform();
    }
 }
die:
  topScoreB = EEPROM.read(0);
  topScoreB = topScoreB << 8;
  topScoreB = topScoreB |  EEPROM.read(1);

  if (score > topScoreB) { 
    topScoreB = score;
    EEPROM.write(1,score & 0xFF); 
    EEPROM.write(0,(score>>8) & 0xFF); 
    newHigh = 1;
    }
  }

void drawPlatform(){
 ssd1306_setpos(player,7);
 ssd1306_send_data_start();
 ssd1306_send_byte(B00000000);   
 ssd1306_send_byte(B00000000);   
 for (byte pw = 0; pw <5; pw++){ssd1306_send_byte(B11000000);}                
 for (byte pw = 0; pw <4; pw++){ssd1306_send_byte(B11110000);}                
 for (byte pw = 0; pw <5; pw++){ssd1306_send_byte(B11000000);}                
 ssd1306_send_byte(B00000000);   
 ssd1306_send_byte(B00000000);   
 ssd1306_send_data_stop();  
}

void sendBlock(int fill){
  if (fill == 1) {
   ssd1306_send_byte(B10011000);
   ssd1306_send_byte(B01011100);
   ssd1306_send_byte(B10110110);
   ssd1306_send_byte(B01011111);
   ssd1306_send_byte(B01011111);
   ssd1306_send_byte(B10110110);
   ssd1306_send_byte(B01011100);
   ssd1306_send_byte(B10011000);
  } else if (fill == 2) {
   ssd1306_send_byte(B00110000);
   ssd1306_send_byte(B00111110);
   ssd1306_send_byte(B10110011);
   ssd1306_send_byte(B01011101);
   ssd1306_send_byte(B01011101);
   ssd1306_send_byte(B10110011);
   ssd1306_send_byte(B00111110);
   ssd1306_send_byte(B00110000);  
  } else if (fill == 3) {
   ssd1306_send_byte(B00011000);
   ssd1306_send_byte(B00111000);
   ssd1306_send_byte(B00110100);
   ssd1306_send_byte(B00110100);
   ssd1306_send_byte(B00110100);
   ssd1306_send_byte(B00110100);
   ssd1306_send_byte(B00111000);
   ssd1306_send_byte(B00011000);  
  } else if (fill == 0) {
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
   ssd1306_send_byte(B00000000);
  } 
}

void levelUp(int number) {

  fire = 0; // make sure no fire
  playerFire[0] = 0; // player fire inactive
  aliencounter=0;
  firecounter=0;
  mothercounter=0;
  firstAlien = 0;
  lastAlien = 8;
  newFirst = 0;
  newLast = 8;
  lastActiveRow = 2;
  deadOn1 = 0;
  deadOn2 = 0;
  aliensDead = 0;      
  mothership = 0;
  alienRow = 0;
  positionNow = 0;
  alienDirection = 1;
  player = 64;

  ssd1306_fillscreen(0x00);
  ssd1306_char_f6x8(16, 3, "--------------");
  ssd1306_char_f6x8(16, 4, " L E V E L ");
  ssd1306_char_f6x8(16, 5, "--------------");
  doNumber(85,4,number);
  for (int i = 800; i>200; i = i - 200){
  beep(30,i);
  }
  delay(700);    
  ssd1306_fillscreen(0x00);
}

void drawFire(int x, int y) {
  if (y%8!=0){
    ssd1306_setpos(x,y/8);
    ssd1306_send_data_start();
    doDrawLS(0,y%8);
    ssd1306_send_data_stop();
    
    ssd1306_setpos(x,y/8+1);
    ssd1306_send_data_start();
    doDrawRS(0,8-y%8);
    ssd1306_send_data_stop();
  } else {
    ssd1306_setpos(x,y/8);
    ssd1306_send_data_start();
    doDrawLS(0,0);
    ssd1306_send_data_stop();
  }
}

// Drawing routine for the player and fire - with right-shifts
void doDrawRS(long P1, byte P2) {
  ssd1306_send_byte((B01111110 | P1)>>P2);
}

// Drawing routine for the player and fire - with left-shifts
void doDrawLS(long P1, byte P2) {
  ssd1306_send_byte((B01111110 | P1)<<P2);
}

void clearAlienArea(int row, int lastActive) {
  // clear alien area
  for (int inc = row; inc <=row+lastActive; inc ++) {
    ssd1306_setpos(0,inc);
    ssd1306_send_data_start();
    for (int bl = 0; bl <16; bl++){
      sendBlock(0);
      }   
      ssd1306_send_data_stop();
    }
}

void resetAliens(void) {
  for (byte i =0; i<10;i++){ // reset aliens
    row[0][i]=0; row[1][i]=0; row[2][i]=0;
  } 
  for (byte i =0; i<9;i+=2){ // reset aliens
    row[0][i]=1; row[2][i]=1;
  } 
  for (byte i =1; i<9;i+=2){ // reset aliens
    row[1][i]=1;
  }     
}

/*
 * SSD1306xLED - Drivers for SSD1306 controlled dot matrix OLED/PLED 128x64 displays
 *
 * @file: font6x8.h
 * @created: 2014-08-12
 * @author: Neven Boyanov
 * 
 * Hacked by andy jackson to allow two games (originally by webboggles.com) to 
 * fit onto an ATTiny85 at the same time - hence several characters are missing
 * and a couple have been moved to limit the amount of software remapping required
 * to map ASCII values onto locations in this array.
 *
 * Source code available at: https://bitbucket.org/tinusaur/ssd1306xled
 *
 */

// ----------------------------------------------------------------------------

#include <avr/pgmspace.h>

// ----------------------------------------------------------------------------

/* Standard ASCII 6x8 font */
static const uint8_t ssd1306xled_font6x8 [] PROGMEM = {
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // sp
/*
  0x00, 0x00, 0x00, 0x2f, 0x00, 0x00, // !
  0x00, 0x00, 0x07, 0x00, 0x07, 0x00, // "
  0x00, 0x14, 0x7f, 0x14, 0x7f, 0x14, // #
  0x00, 0x24, 0x2a, 0x7f, 0x2a, 0x12, // $
  0x00, 0x62, 0x64, 0x08, 0x13, 0x23, // %
  0x00, 0x36, 0x49, 0x55, 0x22, 0x50, // &
  0x00, 0x00, 0x05, 0x03, 0x00, 0x00, // '
  0x00, 0x00, 0x1c, 0x22, 0x41, 0x00, // (
  0x00, 0x00, 0x41, 0x22, 0x1c, 0x00, // )
  0x00, 0x14, 0x08, 0x3E, 0x08, 0x14, // *
  0x00, 0x08, 0x08, 0x3E, 0x08, 0x08, // +
  0x00, 0x00, 0x00, 0xA0, 0x60, 0x00, // ,
  */
  0x00, 0x08, 0x08, 0x08, 0x08, 0x08, // -
  0x00, 0x00, 0x60, 0x60, 0x00, 0x00, // .
  0x00, 0x3C, 0x40, 0x30, 0x40, 0x3C, // w in place of /
  //0x00, 0x20, 0x10, 0x08, 0x04, 0x02, // /
  0x00, 0x3E, 0x51, 0x49, 0x45, 0x3E, // 0
  0x00, 0x00, 0x42, 0x7F, 0x40, 0x00, // 1
  0x00, 0x42, 0x61, 0x51, 0x49, 0x46, // 2
  0x00, 0x21, 0x41, 0x45, 0x4B, 0x31, // 3
  0x00, 0x18, 0x14, 0x12, 0x7F, 0x10, // 4
  0x00, 0x27, 0x45, 0x45, 0x45, 0x39, // 5
  0x00, 0x3C, 0x4A, 0x49, 0x49, 0x30, // 6
  0x00, 0x01, 0x71, 0x09, 0x05, 0x03, // 7
  0x00, 0x36, 0x49, 0x49, 0x49, 0x36, // 8
  0x00, 0x06, 0x49, 0x49, 0x29, 0x1E, // 9
  0x00, 0x00, 0x36, 0x36, 0x00, 0x00, // :
/*
  0x00, 0x00, 0x56, 0x36, 0x00, 0x00, // ;
  0x00, 0x08, 0x14, 0x22, 0x41, 0x00, // <
  0x00, 0x14, 0x14, 0x14, 0x14, 0x14, // =
  0x00, 0x00, 0x41, 0x22, 0x14, 0x08, // >
  0x00, 0x02, 0x01, 0x51, 0x09, 0x06, // ?
  0x00, 0x32, 0x49, 0x59, 0x51, 0x3E, // @
 */
  0x00, 0x7C, 0x12, 0x11, 0x12, 0x7C, // A
  0x00, 0x7F, 0x49, 0x49, 0x49, 0x36, // B
  0x00, 0x3E, 0x41, 0x41, 0x41, 0x22, // C
  0x00, 0x7F, 0x41, 0x41, 0x22, 0x1C, // D
  0x00, 0x7F, 0x49, 0x49, 0x49, 0x41, // E
  0x00, 0x7F, 0x09, 0x09, 0x09, 0x01, // F
  0x00, 0x3E, 0x41, 0x49, 0x49, 0x7A, // G
  0x00, 0x7F, 0x08, 0x08, 0x08, 0x7F, // H
  0x00, 0x00, 0x41, 0x7F, 0x41, 0x00, // I
  0x00, 0x20, 0x40, 0x41, 0x3F, 0x01, // J
  0x00, 0x7F, 0x08, 0x14, 0x22, 0x41, // K
  0x00, 0x7F, 0x40, 0x40, 0x40, 0x40, // L
  0x00, 0x7F, 0x02, 0x0C, 0x02, 0x7F, // M
  0x00, 0x7F, 0x04, 0x08, 0x10, 0x7F, // N
  0x00, 0x3E, 0x41, 0x41, 0x41, 0x3E, // O
  0x00, 0x7F, 0x09, 0x09, 0x09, 0x06, // P
  0x00, 0x3E, 0x41, 0x51, 0x21, 0x5E, // Q
  0x00, 0x7F, 0x09, 0x19, 0x29, 0x46, // R
  0x00, 0x46, 0x49, 0x49, 0x49, 0x31, // S
  0x00, 0x01, 0x01, 0x7F, 0x01, 0x01, // T
  0x00, 0x3F, 0x40, 0x40, 0x40, 0x3F, // U
  0x00, 0x1F, 0x20, 0x40, 0x20, 0x1F, // V
  0x00, 0x3F, 0x40, 0x38, 0x40, 0x3F, // W
/*
  0x00, 0x63, 0x14, 0x08, 0x14, 0x63, // X
  0x00, 0x07, 0x08, 0x70, 0x08, 0x07, // Y
  0x00, 0x61, 0x51, 0x49, 0x45, 0x43, // Z
  0x00, 0x00, 0x7F, 0x41, 0x41, 0x00, // [
  0x00, 0x55, 0x2A, 0x55, 0x2A, 0x55, // 55
  0x00, 0x00, 0x41, 0x41, 0x7F, 0x00, // ]
  0x00, 0x04, 0x02, 0x01, 0x02, 0x04, // ^
  0x00, 0x40, 0x40, 0x40, 0x40, 0x40, // _
  0x00, 0x00, 0x01, 0x02, 0x04, 0x00, // '
*/
  0x00, 0x20, 0x54, 0x54, 0x54, 0x78, // a
  0x00, 0x7F, 0x48, 0x44, 0x44, 0x38, // b
  0x00, 0x38, 0x44, 0x44, 0x44, 0x20, // c
  0x00, 0x38, 0x44, 0x44, 0x48, 0x7F, // d
  0x00, 0x38, 0x54, 0x54, 0x54, 0x18, // e
  0x00, 0x08, 0x7E, 0x09, 0x01, 0x02, // f
  0x00, 0x18, 0xA4, 0xA4, 0xA4, 0x7C, // g
  0x00, 0x1C, 0xA0, 0xA0, 0xA0, 0x7C, // y (in place of h)
  //0x00, 0x7F, 0x08, 0x04, 0x04, 0x78, // h
  0x00, 0x00, 0x44, 0x7D, 0x40, 0x00, // i
  0x00, 0x40, 0x80, 0x84, 0x7D, 0x00, // j
  0x00, 0x7F, 0x10, 0x28, 0x44, 0x00, // k
  0x00, 0x00, 0x41, 0x7F, 0x40, 0x00, // l
  0x00, 0x7C, 0x04, 0x18, 0x04, 0x78, // m
  0x00, 0x7C, 0x08, 0x04, 0x04, 0x78, // n
  0x00, 0x38, 0x44, 0x44, 0x44, 0x38, // o
  0x00, 0xFC, 0x24, 0x24, 0x24, 0x18, // p
  0x00, 0x18, 0x24, 0x24, 0x18, 0xFC, // q
  0x00, 0x7C, 0x08, 0x04, 0x04, 0x08, // r
  0x00, 0x48, 0x54, 0x54, 0x54, 0x20, // s
  0x00, 0x04, 0x3F, 0x44, 0x40, 0x20, // t
  0x00, 0x3C, 0x40, 0x40, 0x20, 0x7C, // u
  0x00, 0x1C, 0x20, 0x40, 0x20, 0x1C, // v
 // 0x00, 0x3C, 0x40, 0x30, 0x40, 0x3C, // w
 // 0x00, 0x44, 0x28, 0x10, 0x28, 0x44, // x
 // 0x00, 0x1C, 0xA0, 0xA0, 0xA0, 0x7C // y
};

// ----------------------------------------------------------------------------

Credits

Arnov Sharma

308 projects • 306 followers

Just your average MAKER

Candy Box Gameboy

Things used in this project

Hardware components

Story

Material Required

Design

Preparing the Box

PCB Design

PCBWAY

Solderpaste Dispensing and Pick & Place Process

Hotplate Reflow

THT Process

Adding PCB Standoffs to Board

Adding OLED Display

Result so far

Programming Attiny85

GAME

Final Assembly

END RESULT

Schematics

sch

Code

ATTBOY.ino

font6x8AJ.h

Credits

Arnov Sharma

Comments

Embed the widget on your own site

Candy Box Gameboy

Candy Box Gameboy

Things used in this project

Hardware components

Story

Material Required

Design

Preparing the Box

PCB Design

PCBWAY

Solderpaste Dispensing and Pick & Place Process

Hotplate Reflow

THT Process

Adding PCB Standoffs to Board

Adding OLED Display

Result so far

Programming Attiny85

GAME

Final Assembly

END RESULT

Schematics

sch

Code

ATTBOY.ino

font6x8AJ.h

Credits

Arnov Sharma

Comments

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