Is there a way to turn off all pins of one 595 shift register but not the others

Other Hardware LEDs and Multiplexing
1

Is there a command that will let me set all 8 output pins of a 595 to LOW without affecting the three other 595s I have chained together?

I'm using this conditional to check if the signal is in the same bank:

if((i % 8) == (pinNumber % 8))

And then if the condition is true, I need to set those pins LOW...

Here is my function for the shiftOut:

void registerWrite(int whichPin, int whichState) {

  // the bits you want to send
   static int bitsToSend = 0;
   static int bitsToSend2 = 0;

  // turn off the output so the pins don't light up
  // while you're shifting bits:
  digitalWrite(latchPin, LOW);

  //CHoose which shift register to send to.
  if (whichPin <=15){
  bitWrite(bitsToSend, whichPin, whichState);
  } else {
  bitWrite(bitsToSend2, whichPin - 16, whichState);
  }

// shift the bytes out:
  shiftOut(dataPin, clockPin, MSBFIRST, bitsToSend2 >> 8);
  shiftOut(dataPin, clockPin, MSBFIRST, bitsToSend2 & 0xff);
  shiftOut(dataPin, clockPin, MSBFIRST, bitsToSend >> 8);
  shiftOut(dataPin, clockPin, MSBFIRST, bitsToSend & 0xff);

    // turn on the output so the LEDs can light up:
  digitalWrite(latchPin, HIGH);

}
2

mbira:
Is there a command that will let me set all 8 output pins of a 595 to LOW without affecting the three other 595s I have chained together?

If the four shift registers are daisy-chained, as you say, there is no good way to set the outputs of one register to all 0's without loading the other three registers at the same time. Typically that is how it's done. If speed is a problem you can use the SPI hardware to shift out data at millions of bits per second.

If you want to load registers individually you could use a different Clock pin for each. They can share a data pin and a Latch pin because they won't do anything without pulses on the Clock pin.