Output Expander Module.ino

/*Output Expander Module

This program converts a serial into a parallel output with 8 output ports per board. 
Each output ports has LED state indicators.
+3.3V or +5V of the microcontroller may be used.
This module is usually used with an input expander module.

JP2 pin assignments:
Din on digital pin 8
Str on digital pin 9
Clk on digital pin 10
VDD on +5V

Codes by:
Dan
eGizmo Mechatronix Central
Manila, Philippines
April 3, 2013

*/

// Constants
const int DataIN =  8; 
const int StrIN = 9;
const int ClkIN = 10;



void setup()
{
  pinMode(DataIN, OUTPUT); // Pin 8 as output
  pinMode(ClkIN, OUTPUT); // Pin 9 as output
  pinMode(StrIN, OUTPUT); // Pin 10 as output
}


void loop()
{
  for(int i = 0; i<=256; i++)
  {
    shiftOut(i);
    // Set cycle for strobe in
    digitalWrite(StrIN, HIGH);
    digitalWrite(StrIN,LOW);
    delay(500);
  }
}

void shiftOut(byte DataOUT) // Sets a byte called DataOUT
{
  boolean state;
  
  // Sets the cycle for data in and clock in
  digitalWrite(DataIN, LOW);
  digitalWrite(ClkIN, LOW);

  for (int i=0; i<=7; i++) 
  // This is set for 8bit binary.
  {
    digitalWrite(ClkIN, LOW);
    if (DataOUT&(1<<i)) 
    {
      state = HIGH;
    }
    else 
    {
      state = LOW;
    }

    digitalWrite(DataIN, state);
    digitalWrite(ClkIN, HIGH);
  }

  digitalWrite(ClkIN,LOW);
  }