Millis() and i2c interrupt issue

Projects Programming
5

Apologies. I have stripped everything not needed from the script to keep it really simple and confirmed that this exhibits the same issue.

Code for master:

#include <Wire.h>

void setup() {
  Wire.begin();
  Wire.setClock(400000L);
  Serial.begin(115200);//For testing only
}

void loop() {
  unsigned long lastMillisSlave=0;
  
  if((unsigned long)(millis()-lastMillisSlave)>=50){
    lastMillisSlave=millis();
    requestStatusFromSlave();
  }
}

void requestStatusFromSlave(){
  Serial.println("Requesting status");
  Wire.requestFrom(1, 32);
  
  while(Wire.available()){
    char c=Wire.read();
    Serial.print(c);
  }
  Serial.println("");
}

And Slave *** this is the one that will give the serial output of the error:

#include <Wire.h>

volatile unsigned long lastUpdateMillis=0;

void setup() {
  Wire.begin(1);
  Wire.setClock(400000L);
  Wire.onRequest(requestStatus);
  Serial.begin(115200);//For testing only
}

void loop() {
  unsigned long thisNum=millis()-lastUpdateMillis;
  if(thisNum>=2000){
    Serial.print("thisNum is ");
    Serial.println(thisNum);
    Serial.print("Millis is ");
    Serial.println(millis());
    Serial.print("lastUpdateMillis is  ");
    Serial.println(lastUpdateMillis);
    
    //Turn off all digital IOs
  }
}

/* Report status back to Master */
void requestStatus(){
  lastUpdateMillis=millis();
  
  for(byte i=0;i<32;i++) Wire.write("A");
}