int timer = 1500; // the amount of time each portion of the array is on
int nMosPins[] = { // location of nMOSFET pins
  3,2,1,0};
int nMosCount = 4; // number of nMOSFET pins
int pMosPins[] = { // location of p MOSFET pins
  4,7,5};
int pMosCount = 3; // number of pMOSFET pins
int ledPin = 8;

void setup(){
  for (int nPin = 0; nPin < nMosCount; nPin++){ //initiate nMos pins as outputs
    pinMode(nMosPins[nPin], OUTPUT);}
  
  for (int pPin = 0; pPin < pMosCount; pPin++){ //initiate pMos pins as outputs
    pinMode(pMosPins[pPin], OUTPUT);
    digitalWrite(pMosPins[pPin], HIGH);
 }
   pinMode(ledPin, OUTPUT);
 }
  
void loop(){
  for (int i = 0; i < pMosCount; i++){
   digitalWrite(pMosPins[i], LOW); 
   digitalWrite(ledPin, HIGH);
      for (int j = 0; j < nMosCount; j++){
        digitalWrite(nMosPins[j], HIGH);
        delay(timer);
        digitalWrite(nMosPins[j],LOW);
       }
     digitalWrite(pMosPins[i], HIGH);
     digitalWrite(ledPin, LOW);
     delay(500);
   }
 }