Read the function generator trigger via GPIB using Arduino Mega

[kikissko]

Hello All,
I have a not so typical task, I need to read 'data transfer' and EOI from GPIB (IEEE-488) using Arduino Mega. Basically, I'm triggering a function generator and I'm connected to the Arduino via GPIB.
What I want to do it's to read 8 bits (byte) from GPIB but only when EOI is 1, because in that case I have trigger active.
I have a code but it's not enough advanced. I am not sure is it my code not good enough to read when EOI is 1 (it's 1 just 300us), or my Arduino is to slow? Sometimes I am able to read EOI=1 but i get value of just fist byte and that's all.

pic of the trigger

[UKHeliBob]

Welcome to the forum

@kikissko

I have a code

Please post it, using code tags when you do

[horace]

try a web search for arduino iee488 you should get plenty of links to AR488 GPIB interface

[kikissko]

const int DIO[] = {22, 23, 24, 25, 26, 27, 28, 29};
const int EOI_PIN = 38;
int bitValue[8]; // Declare bitValue as a global array

void setup() {
  Serial.begin(9600);
  for (int i = 0; i < 8; i++) {
    pinMode(DIO[i], INPUT);
  }
  pinMode(EOI_PIN, INPUT);

  int registerValue = PORTA;
  
  for (int i = 0; i < 8; i++) {
    int bitNumber = i;
    int bitValue = bitRead(registerValue, bitNumber);
    Serial.print("Value of bit ");
    Serial.print(bitNumber);
    Serial.print(" in PORTA: ");
    Serial.println(bitValue, BIN);
  }
 }

void loop() {
 int eoi = digitalRead(EOI_PIN);
  delayMicroseconds(10);
  if(eoi == 1) {
     Serial.println(eoi, BIN);
     // Use bitValue array in the loop code
 /* for (int i = 0; i < 8; i++) {
    if (bitValue[i] == 1) {
      // Do something if the bit is HIGH
       Serial.println(bitValue[i], BIN);
    }
    else {
      // Do something else if the bit is LOW
       Serial.println(bitValue[i], BIN);
    }
  }*/
  /*  int val[8];
    for (int i = 0; i < 8; i++) {
      val[i] = digitalRead(bitValue[i]);
      Serial.print("DIO");
      Serial.print(i+1);
      Serial.print(":");
      Serial.println(val[i], BIN);
    }*/
    
   // Serial.println(val[], BIN);
 //delayMicroseconds(10);
  }
  else if (eoi == 0){
   Serial.println(eoi, BIN);type or paste code here
   Serial.println("It is no longer 1");
  // delayMicroseconds(50);
   }
}

[kikissko]

const int DIO[] = {22, 23, 24, 25, 26, 27, 28, 29};
const int EOI_PIN = 38;

void setup() {
  Serial.begin(9600);
  for (int i = 0; i < 8; i++) {
    pinMode(DIO[i], INPUT);
  }
  pinMode(EOI_PIN, INPUT);
}

void loop() {
 int eoi = digitalRead(EOI_PIN);
  if(eoi == 1) {
    Serial.println(eoi, BIN);
    int val[8];
    for (int i = 0; i < 8; i++) {
      val[i] = digitalRead(DIO[i]);
      Serial.print("DIO");
      Serial.print(i+1);
      Serial.print(":");
      Serial.println(val[i], BIN);
    }
    
   // Serial.println(val[], BIN);
    delayMicroseconds(10);
  }
}

[kikissko]

I have those two, one when i tried to read as a bit and one as a digitalRead, I am not sure do i need to use Timer1 and register?