Adafruit fingerprint code explanation

Projects Programming
7

THX, I found it. Or something enough like it. It does indeed write off the end of the array.

I copied and pasted the snippet into a "real" C program context using an online interpreter. Changed but I feel certain not damaged to illustrate, viz:

# include <stdio.h>

//   uint8_t fingerTemplate[512]; // the real template

int main()
{
    printf("Hello World\n");
    
    int uindx = 9, index = 0;
    while (index < 534) {
        while (index < uindx) ++index;
        uindx += 256;
        while (index < uindx) {
 //                 fingerTemplate[index++] = bytesReceived[index];
 
            printf("writing into fingerTemplate at index %d.\n", index);
            index++;
      }
      uindx += 2;
      while (index < uindx) ++index;
      uindx = index + 9;
  }

    return 0;
}

The last line of output reads

writing into fingerTemplate at index 531.

Oops, as is said. :expressionless:

Sometimes errors like that do not cause immediate problems. So are not seen, but can manifest at any point and be tots unrelated to the problem(s) they cause.

a7

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