TPIC6B595 Shift Registers Controlling Multiple Steppers

Projects General Guidance
23

Ok here's my code, please see the commented out part "where I'm lost".
Thanks again.

/*
  Nano | TPIC6B595
    5V | 2 (VCC)
   GND | GND
    D8 | 8 (SRCLR)
   D10 | 12 (RCK)
   D11 | 3 (SER IN) of the first chip
   D13 | 13 (SRCK)
       | 9 to GND
       | 10, 11,19 to GND
       | 18 (SER OUT) to 3 of the next chip
*/

#include <SPI.h>
#include <EEPROM.h>

const byte motors = 41; // sets of four motors
const byte clrPin = 8; // TPIC6B595 SRCLR pin8
const byte latchPin = 10; // TPIC6B595 RCK pin12

int CurrPos;  // current position
int NewPos;  // new position to go to
int RandNum;  // random number
int steps;   // will hold number of steps to reach a target position

int sensor = 2;              // the pin that the sensor is atteched to
int state = LOW;             // by default, no motion detected
int val = 0;                 // variable to store the sensor status (value)


int TargetPos[] = {550, 1900, 3080, 2048, 5000, 5500, 6028, 7500}; // hypotetical positions, just for testing

void setup() {
  SPI.begin();
  pinMode(clrPin, OUTPUT);
  pinMode(latchPin, OUTPUT);
  digitalWrite(clrPin, HIGH); // clear all shift register data


  EEPROM.get( 0, CurrPos );  // read tha last known position of the steppers
}

void loop() {

  val = digitalRead(sensor);   // read sensor value
  if (val == HIGH) {           // check if the sensor is HIGH
    Go_To_Target_Pos();
    
  }
}

void Go_To_Target_Pos() {

  randomSeed(analogRead(0));  // generate a random number
  RandNum = random(0, 7); // a numbers equal to numer of positions in array TargetPos
  delay(50);
  NewPos = (TargetPos[RandNum]);

  steps = (NewPos - CurrPos);  // number of steps needed to go from current position to new position

  if (steps < 0) {
  steps = steps * - 1;  // go backwards
}

/*  **********************************************
 >>>>>>   Here's where I'm lost  <<<<<<<<<<

without shift registers I'd write direction pin HIGH/LOW to go forward
or backward, then :

for (int x = 0; x < steps + 1; x++) {
    digitalWrite(step_pin, HIGH);
    delay(10);
    digitalWrite(step_pin, LOW);
}

>>>>>  Using shift registers what is the procedure to send the correct bits 
        to all shift registers to meve all steppers to the NewPos ?

   ***********************************
*/

EEPROM.update(0, NewPos);
state = LOW;       // update variable state to LOW

}