Arduino R4 Minima, trigger function being bypassed?

Question

I am running a trigger function in a while loop in setup that takes in 3 analog inputs, checks if they are within a certain range, then outputs true if they are, false if none of them are. The code I am running was originally written for an arduino mega 2560.

The code works by continuously analogReading to see if all inputs are out of range in a while loop (preBuffer) and if the preBuffer has been filled at least once, then if so reading continuosly to a storage array (buffer).

I am unsure why it seems that the preBuffer trigger function is being skipped.

//standard resolution is 10 bit 0-1023
//#include "avdweb_AnalogReadFast.h"
const long baudRate = 57600; //testing baud rate, up to at least 115200
const int bufferSize = 1000;
const int preBufferSize = 100;
unsigned int a0Pre[preBufferSize];
unsigned int a1Pre[preBufferSize];
unsigned int a2Pre[preBufferSize];
unsigned int a0Buffer[bufferSize];
unsigned int a1Buffer[bufferSize];
unsigned int a2Buffer[bufferSize];
bool inRange(unsigned int val, unsigned int target) {
 const unsigned int trigger = 5;
 return ((target - trigger) <= val) && ((target + trigger) >= val);
}
bool triggerFunction(unsigned int a0, unsigned int a1, unsigned int a2) {
 return (inRange(a0, 517) || inRange(a1, 509) || inRange(a2, 515));
}
unsigned int read (int pin, int delay) {
 delayMicroseconds(delay);
 return analogRead(pin);
}
void rotate1 (unsigned int arr[], const int size) {
 unsigned int target = 0;
 unsigned int prev = arr[size-1];
 for (int i = 0; i < preBufferSize; i++) {
 target = prev;
 prev = arr[i];
 arr[i] = target;
 }
}
void setup()
{
 Serial.begin(baudRate);
 while(!Serial);
 // Record Data points and avg time between data points.
 // Due to sequencing, a1buffer points are 1 meanread time after a0 buffer, and a2buffer points are 2 meanread time after a0 buffer.
 analogReadResolution(10);
 delay(3000);
 Serial.println("Buffer Start");
 //PreBuffer, with trigger logic
 //dummy read
 int j = 0;
 bool notfull = true;
 const int preReadDelay = 5;
 const int readDelay = 5;
 unsigned long preTime1 = 0;
 unsigned long preTime2 = micros();
 while (notfull || (triggerFunction(a0Pre[j-1],a1Pre[j-1],a2Pre[j-1]))) {
 a0Pre[j] = read(A0, preReadDelay);
 a1Pre[j] = read(A1, preReadDelay);
 a2Pre[j] = read(A2, preReadDelay);
 if (j == preBufferSize - 1) {
 notfull = false;
 preTime1 = preTime2;
 preTime2 = micros();
 }
 j = (j + 1) % preBufferSize;
 }
 //Main buffer read
 const unsigned long time1 = micros();
 for (int i = 0; i < bufferSize; i++) {
 a0Buffer[i] = read(A0, readDelay);
 a1Buffer[i] = read(A1, readDelay);
 a2Buffer[i] = read(A2, readDelay);
 }
 const unsigned long time2 = micros();
 const float meanReadTime = (float)(time2 - time1) / (float)bufferSize;
 const float meanReadPreTime = (float)(preTime2 - preTime1) / (float)preBufferSize;
 delay(100);
 // rotate buffer so that trigger is last value
 for (int i = 0; i < (preBufferSize - j - 2) % preBufferSize ; i++) {
 rotate1(a0Pre, preBufferSize);
 rotate1(a1Pre, preBufferSize);
 rotate1(a2Pre, preBufferSize);
 }
 
 //header values
 Serial.print("preBufferSize,");
 Serial.print("bufferSize,");
 Serial.print("preReadFreq,"); 
 Serial.println("readFreq");
 Serial.print(preBufferSize);
 Serial.print(",");
 Serial.print(bufferSize);
 Serial.print(",");
 Serial.print((float)1E6 / meanReadPreTime);
 Serial.print(",");
 Serial.println((float)1E6 / meanReadTime);
 
 Serial.println("Buffer End");
 //column names
 Serial.println("A0,A1,A2,micros");
 for(int i = 0; i < preBufferSize; i ++) {
 Serial.print(a0Pre[i]);
 Serial.print(",");
 Serial.print(a1Pre[i]);
 Serial.print(",");
 Serial.print(a2Pre[i]);
 Serial.print(",");
 Serial.println(meanReadPreTime*i);
 }
 for(int i = 0; i < bufferSize; i ++) {
 Serial.print(a0Buffer[i]);
 Serial.print(",");
 Serial.print(a1Buffer[i]);
 Serial.print(",");
 Serial.print(a2Buffer[i]);
 Serial.print(",");
 Serial.println((meanReadTime*i) + (preBufferSize*meanReadPreTime));
 }
}
void loop() {
 delay(1000);
}

• Edgar Bonet: What makes you believe that the function is skipped?
• Carmeline Wu: Found a major issue that may solve it. arduino mega 2560 and arduino uno r4 seem to have different behavior for %, modulo and remainder respectively. This combined with what seems to be a lock of negative array indexing resulted in my previous issue.
• Carmeline Wu: The code was looked to be skipped as It immediately ran to print serial, when its previous behavior was to wait for a trigger sound, something like a snap. I assumed that due to arm based architecture the arduino was running further code up in parallel thus skipping the trigger, but that turned out not to be the case.
• Edgar Bonet: The modulo operator % is supposed to behave consistently across architectures. If it doesn't, it's a bug. Could you show us a modulo operation that gives different outputs on AVR and ARM?
• jsotola: add debugging code to your program ... determine what actually happens