Questions about 74HC574

Other Hardware General Electronics
1

Hallo everyone,

I am pretty new to arduino- I hope I post this in the correct section.
After some testing I managed to use 2x 74HC595N ( QJ88D4 25 UnG1403D dont know if these numbers are important.), these got 8 pins each side. Then I wanted to build one of these 8x8x8 LED Cubes in these projekts they use simular/same. The ones I ordered had now 10 pins each side ( 35C593KE4 SN74HC574N) .

I didnt find any example wiring for these so here are my questions:

  • How much are these different from how these are working
  • Can I use the same Code which I used for the ones with 8 pins- how to wire it then?
  • How much LEDs could I controll with 10 of these

The code I used for the 8pin model ( from the internet)

int SER_Pin = 8;   //pin 14 on the 75HC595
int RCLK_Pin = 9;  //pin 12 on the 75HC595
int SRCLK_Pin = 10; //pin 11 on the 75HC595

//How many of the shift registers - change this
#define number_of_74hc595s 2 

//do not touch
#define numOfRegisterPins number_of_74hc595s * 8

boolean registers[numOfRegisterPins];

void setup(){
  pinMode(SER_Pin, OUTPUT);
  pinMode(RCLK_Pin, OUTPUT);
  pinMode(SRCLK_Pin, OUTPUT);


  //reset all register pins
  clearRegisters();
  writeRegisters();
}               


//set all register pins to LOW
void clearRegisters(){
  for(int i = numOfRegisterPins - 1; i >=  0; i--){
     registers[i] = LOW;
  }
} 


//Set and display registers
//Only call AFTER all values are set how you would like (slow otherwise)
void writeRegisters(){

  digitalWrite(RCLK_Pin, LOW);

  for(int i = numOfRegisterPins - 1; i >=  0; i--){
    digitalWrite(SRCLK_Pin, LOW);

    int val = registers[i];

    digitalWrite(SER_Pin, val);
    digitalWrite(SRCLK_Pin, HIGH);

  }
  digitalWrite(RCLK_Pin, HIGH);

}

//set an individual pin HIGH or LOW
void setRegisterPin(int index, int value){
  registers[index] = value;
}


void loop(){
  for(int i=0;i<numOfRegisterPins;i++){
  setRegisterPin(i, HIGH);
   writeRegisters();
  delay(100);
  }
   for(int i = numOfRegisterPins - 1; i >=  0; i--){
  setRegisterPin(i, LOW);
   writeRegisters();
  delay(100);
  
 }

  writeRegisters();  //MUST BE CALLED TO DISPLAY CHANGES
  //Only call once after the values are set how you need.
}
2

The 74HC574 is not a shift register, it is an octal D type flipflop.

The way it works is you change the values of the the 8 input pins, then pulse the clock pin to latch the values - then when OE is low, the output pins will output a low or high, depending on which value was latched from the corresponding input pin.

Not very useful for driving LEDs from Arduino! You want the 74HC595, not the 574.

3

Ok thank you alot for explaining

4

You can also google the datasheets for 74HC parts.