Khalid.
Member
B4X:
//Pin connected to ST_CP of 74HC595
int latchPin = 6;
//Pin connected to SH_CP of 74HC595
int clockPin = 13;
////Pin connected to DS of 74HC595
int dataPin = 11;
byte FirstByte;
byte SecondByte;
byte ThirdByte;
byte FourthByte;
byte FifthByte;
int val;
byte serialInArray[5]; // array for storing 3 bytes as they arrive from processing
int serialCount = 0; // for counting the number of bytes received
void setup() {
//Start Serial for debuging purposes
Serial.begin(9600);
//set pins to output because they are addressed in the main loop
pinMode(latchPin, OUTPUT);
}
void loop() {
if (Serial.available() > 0){
serialInArray[serialCount] = Serial.read(); // read a byte sent by processing
serialCount++; // increment number of bytes received
if (serialCount > 4 ) { // when 3 bytes received
FirstByte = serialInArray[0]; // get value for Red LEDs
SecondByte = serialInArray[1]; // get value for Green LEDs
ThirdByte = serialInArray[2];
FourthByte = serialInArray[3];
FifthByte = serialInArray[4];
Serial.print(FirstByte);
Serial.print(SecondByte);
Serial.print(ThirdByte);
Serial.print(FourthByte);
Serial.print(FifthByte);
Serial.println("");
//count up routine
digitalWrite(latchPin, 0);
//count up on GREEN LEDs
//count down on RED LEDs
shiftOut(dataPin, clockPin, FirstByte);
shiftOut(dataPin, clockPin, SecondByte);
shiftOut(dataPin, clockPin, ThirdByte);
shiftOut(dataPin, clockPin, FourthByte);
shiftOut(dataPin, clockPin, FifthByte);
//return the latch pin high to signal chip that it
//no longer needs to listen for information
digitalWrite(latchPin, 1);
serialCount = 0;
delay(20);
}
}
}
void shiftOut(int myDataPin, int myClockPin, byte myDataOut) {
// This shifts 8 bits out MSB first,
//on the rising edge of the clock,
//clock idles low
//internal function setup
int i=0;
int pinState;
pinMode(myClockPin, OUTPUT);
pinMode(myDataPin, OUTPUT);
//clear everything out just in case to
//prepare shift register for bit shifting
digitalWrite(myDataPin, 0);
digitalWrite(myClockPin, 0);
//for each bit in the byte myDataOut�
//NOTICE THAT WE ARE COUNTING DOWN in our for loop
//This means that %00000001 or "1" will go through such
//that it will be pin Q0 that lights.
for (i=7; i>=0; i--) {
digitalWrite(myClockPin, 0);
//if the value passed to myDataOut and a bitmask result
// true then... so if we are at i=6 and our value is
// %11010100 it would the code compares it to %01000000
// and proceeds to set pinState to 1.
if ( myDataOut & (1<<i) ) {
pinState= 1;
}
else {
pinState= 0;
}
//Sets the pin to HIGH or LOW depending on pinState
digitalWrite(myDataPin, pinState);
//register shifts bits on upstroke of clock pin
digitalWrite(myClockPin, 1);
//zero the data pin after shift to prevent bleed through
digitalWrite(myDataPin, 0);
}
//stop shifting
digitalWrite(myClockPin, 0);
}
