ledprojector/src/main.cpp

#include <Arduino.h>

/*
for cheap Chinese 64 dots LED-Projector

Board has unmarked chip in socket - pin layout fits to ATTiny 2313 an 4313
the LEDS are connected to 8 pcs 74HC595


           --u--
RST      1       20  VCC
NC  (0)  2       19  (16) IN  SCK
NC  (1)  3       18  (15) IN  MISO
XTAL     4       17  (14) IN  MOSI
XTAL     5       16  (13) IN
OUT (4)  6       15  (12) IN
OUT (5)  7       14  (11) IN
OUT (6)  8       13  (10) IN
NC  (7)  9       12  (9)  MIC
GND     10       11  (8)  IN
           -----

()   = Arduino Pins
RST  = Reset - 10K to GND, 10uF to VCC
XTAL = 16 MHz Crystal
IN   = switches
MIC  = Input from microphone amplifier (LM358)
*/

/*
   x
  XXXXXXX
 XX XXX XX
XXXXXXXXXXX
X XXXXXXX X
X X     X X
   XX XX
*/

byte invaderA_1[11] = {112,24,125,182,188,60,188,182,125,24,112};

#define LATCHPIN 5
#define DATAPIN 4
#define CLOCKPIN 6
byte ledsData[8];

byte currentled = 0;

void clear() {
  for (int i=0; i < 8; i++) {
    // low is led on
    ledsData[i] = 255;
  }
}

void writebuffer(byte ledNr) {
  byte chipNr = ledNr / 8;
  byte pinNr = ledNr % 8;
  if(chipNr < 8) {
    bitWrite(ledsData[chipNr], pinNr, LOW);
  }
}

void writexy(byte x, byte y) {
  byte lednr = x*8 + y;
  writebuffer(lednr);
}

byte rowmask[8] = {5,3,1,0,2,4,6,7};
void pushout() {
  digitalWrite(LATCHPIN, LOW);
  for(int i = 8-1; i>=0; i--) {
      byte row = rowmask[i];
      shiftOut(DATAPIN, CLOCKPIN, MSBFIRST, ledsData[row]);
  }
  digitalWrite(LATCHPIN, HIGH);
}

void setup() {
  pinMode(LATCHPIN, OUTPUT);
  pinMode(DATAPIN, OUTPUT);
  pinMode(CLOCKPIN, OUTPUT);

  clear();
  pushout();
}

void drawinvader(int xposition, int yposition) {
  // TODO yposition

  for (int x=0; x<=11; x++) {
    int screenx = x+xposition;
    if (screenx >=0 && screenx < 8) {
      for (int y=0; y<8; y++) {
        int screeny = y+yposition;
        if (screeny >=0 && screeny < 8) {
          if (bitRead(invaderA_1[x],y) == HIGH ) {
            writexy(screenx,screeny);
          }
        }
      }
    }
  }
}


byte currentcol=1;
bool direction = true;

int invaderstart = -12;
int invaderend   = 8;
int invaderposition = invaderstart;

void loop() {
  clear();

  /*
  // x-line
  for(byte i=0; i<8; i++) {
    writexy(i,currentcol-1);
  }
  // y line
  for(byte i=0; i<8; i++) {
    writexy(currentcol-1,i);
  }
  */

  drawinvader(invaderposition,0);

  invaderposition++;
  if (invaderposition >=invaderend) {
    invaderposition = invaderstart;
  }

  pushout();

/*
  if(direction) {
    currentcol++;
  } else {
    currentcol--;
  }
  if (currentcol >8) {
    currentcol = 7;
    direction = false;
  }
  if (currentcol <=0) {
    currentcol=2;
    direction = true;
  }
  */
  delay(300);
}