#define PIN_CLK   2
#define PIN_ADD0  3
#define PIN_ADD1  4
#define PIN_OE    5
#define PIN_LAT   6
#define PIN_D1  7
#define PIN_D2  8


int ct = 0; // test counter

void setup() {
  for (int i = 0; i < 7; i ++) {
    pinMode(2 + i, OUTPUT);
    digitalWrite(2 + i, LOW);
  }
  digitalWrite(PIN_OE, LOW);

  // test 1
  // set A0 and A1 to 0 0
  // controls bank to push vals to.
  // 3
  // 2
  // 1
  // 0
  // etc
  digitalWrite(PIN_ADD0, 0);
  digitalWrite(PIN_ADD1, 0);
  // each bank consists of 128 leds
  // d1 is data for bottom half of display
  // d2 is data for top half

  // shifting data:
  // each bank is further split into chunks
  // 0 pixel is bottom right, proceeds to left until hitting 8
  // row then changes to row+4 and continues from column 0
  // colour then changes to next in cycle
  // data is BBBBBBBB BBBBBBBB GGGGGGGG GGGGGGGG RRRRRRRR RRRRRRRR
  //         | row 0 | row 4  | row 0  | row 4  | row 0  | row 4

}

void loop() {
  //turn off display
  digitalWrite(PIN_OE, HIGH);
  //set latch low to send data
  digitalWrite(PIN_LAT, LOW);
  ct++;
  ct %= 384;

  //think of each bank as 384 alternating rgb leds. Turn each one on in turn
  // this will do both upper and lower panels at the same time
  for (int i = 0; i < 384; i++) {  // led index
    if (i == ct) {
      digitalWrite(PIN_D1, 1);
      digitalWrite(PIN_D2, 1);
    } else {
      digitalWrite(PIN_D1, 0);
      digitalWrite(PIN_D2, 0);

    }
    // toggle clock
    digitalWrite(PIN_CLK, LOW);
    digitalWrite(PIN_CLK, HIGH);

  }



  // flip the latch
  digitalWrite(PIN_LAT, HIGH);
  digitalWrite(PIN_LAT, LOW);

  // turn on display
  digitalWrite(PIN_OE, LOW);

  delay(200);
}