Can't understand this codes process

Question

 void loop()
 {
 if ( Serial.available() > 0 )
 {
 static char input[inputLength];
 static uint16_t i;
 char c = Serial.read();
 if ( c != '\n')
 input[i++] = c;
 else
 {
 input[i] = '0円';
 i = 0;
 uint16_t array[80];
 uint16_t j = 0;
 if ( !strncmp(input, "SEND", 4) )
 {
 char* p = input + 4;
 while ( (p = strchr(p, ' ')) != NULL )
 array[j++] = strtol(p, &p, 16);
 ir_start(array);
 Serial.println("WURKS");
 }
 }
 }
}

Hello I can't seem to figure out what this code is doing. I know the main goal but I can't figure out the proccess. If someone could please make the code dumber for me I would appreciate it :). Full code is here since its hard to copy code: https://anonfiles.com/z6ldWff0pf/no_lib_ino

• chrisl: Sorry, I don't want to download some random file from a random site. Please include all relevant code into your question. Where did you get that code? I stumble across the while loop. I currently don't see how this would work, as `p = strchr(p, ' ') will set the pointer p to the next occurrence of a space character. Then the code tries to convert that space character as a hexadecimal string to an integer. Are you sure, that is code actually works?
• Macaroni: Yes im sure it works :)

Answer 1

It's easier to follow if you indent it properly. I'll do that, and add comments as I go:

void loop() {
 if ( Serial.available() > 0 ) { // If there is something in the serial RX buffer
 static char input[inputLength]; // Create a working string to store data in
 static uint16_t i; // This is the current index in that working string
 char c = Serial.read(); // Read the next character from serial
 if ( c != '\n') // If it's not a "line feed" character...
 input[i++] = c; // then store it in the input string and increment i
 else { // Otherwise...
 
 input[i] = '0円'; // Terminate the string with a NULL to make it valid C
 i = 0; // Reset the index to 0 ready for next time
 uint16_t array[80]; // Create an 80-int array (temporary)
 uint16_t j = 0; // And an index variable
 if ( !strncmp(input, "SEND", 4) ) { // If the string starts with SEND
 char* p = input + 4; // create a "pointer" to the string that starts 4 characters in
 while ( (p = strchr(p, ' ')) != NULL ) // While there is a space somewhere in the string
 array[j++] = strtol(p, &p, 16); // convert the first portion to a number, store it in the array, and advance the pointer to the next space.
 ir_start(array); // Send the array through IR
 Serial.println("WURKS"); // Tell us it worked
 }
 }
 } 
}

So you see it receives data through serial and stores it, byte by byte, in input until it receives \n at which point it looks to see if it starts with SEND, then effectively "cuts off" the SEND by only considering everything after the SEND. Then it slices the remainder of the string up by looking for the next space each time and convert each portion to an integer which it stores in an array.

It then sends that array.

Answer 2

I was dumb, turns out it was converting the hex into a int. I sent the array through serial and looked at it.