can we pair daisy chainning-74hc595 output.

i build new type stopwatch with 2, 7 segment display with 5 digit.my problem is how to display the both display with same number.i try add the output,that mean the data,clock and lath output have double pin.but it can't work.let see the code.
////////////////////////////////////

unsigned long currentmicros = 0;
unsigned long previousmicros = 0;
unsigned long interval = 1000;
unsigned long elapsedmicros = 0;

byte trigger = 2;
byte started = 0;
byte stopped = 0;

byte latchpin = 7, 8; // connect to pin 12 on the 74HC595
byte clockpin = 6, 12; // connect to pin 11 on the 74HC595
byte datapin = 5, 11; // connect to pin 14 on the 74HC595

int ones_seconds = 0;
int tens_seconds = 0;
int ones_minutes = 0;
int tens_minutes = 0;
int tenths = 0;
int hundredths= 0;
int thousandths = 0;

byte inPinstat;
int segdisp[10] = {
63,6,91,79,102,109,125,7,127,111 }; //segment references using 74HC595 Shift Registers
//The above numbers light up different segments of a digit

int time_update = 0;// added new flag
void setup()
{
Serial.begin(115200);

pinMode(latchpin, OUTPUT);
pinMode(clockpin, OUTPUT);
pinMode(datapin, OUTPUT);
pinMode(trigger, INPUT);////stat/stop.

digitalWrite(latchpin, LOW); // send the digits down to the shift registers!
shiftOut(datapin, clockpin, MSBFIRST, segdisp[tens_seconds]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[ones_seconds]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[tenths]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[hundredths]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[thousandths]);
digitalWrite(latchpin, HIGH);
}

void loop()
{

inPinstat = digitalRead(trigger);
if(inPinstat == HIGH)
{
currentmicros = micros(); // read the time.
elapsedmicros = currentmicros - previousmicros;

if (elapsedmicros >= interval) // 10 milliseconds have gone by
{
previousmicros = previousmicros + elapsedmicros; // save the time for the next comparison
time_update = 1; // set flag to shift out the new time
}

if (time_update == 1){ // no updating if not at 10ms interval, skip this whole section
// increment the counters, roll as needed, shift the digits out

time_update = 0; // reset for next pass thru

thousandths = thousandths +1;
if (thousandths == 10){
thousandths = 0;
hundredths = hundredths +1;
}
if (hundredths == 10){
hundredths = 0;
tenths = tenths +1;
}

if (tenths == 10){
tenths = 0;
ones_seconds = ones_seconds +1;
}

if (ones_seconds == 10){
ones_seconds = 0;
tens_seconds = tens_seconds +1;
}

if (tens_seconds == 6){
tens_seconds = 0;
ones_minutes = ones_minutes +1;
}
digitalWrite(latchpin, LOW); // send the digits down to the shift registers!
shiftOut(datapin, clockpin, MSBFIRST, segdisp[tens_seconds]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[ones_seconds]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[tenths]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[hundredths]);
shiftOut(datapin, clockpin, MSBFIRST, segdisp[thousandths]);
digitalWrite(latchpin, HIGH);
}
}
}

Hi, please edit your post and add code tags around your sketch. Use the # button above the edit box.

This part of your sketch makes no sense to me:

byte latchpin = 7, 8; // connect to pin 12 on the 74HC595
byte clockpin = 6, 12;  // connect to pin 11 on the 74HC595
byte datapin = 5, 11; // connect to pin 14 on the 74HC595

If you want both displays to show the same number always, you do not need to use extra Arduino outputs. You can connect both displays to the same Arduino outputs. If you sometimes want to display different numbers on the displays, you can either use more Arduino outputs, or you can daisy-chain one display after the other display.

Paul

Thank you very much Paul.
Work perfect.just connect the cable both to arduino output and we will the same number.
I will show it if I'm done the hardware part.