how high does a 16 bit binary counter count?

The highest number is 65535, then 0, then 105.

Or:

d = 105 - 65507;

if (d < 0) d = d + 65536

Thus, in your case, the answer is 134.

To check this, from 65535 to 1 should be 2... 65535, 0, 1

A 16 bit binary counter counts up to 65535 ( i.e 2^16-1).

It depends on how many times it reset. When it resets, it should go from 2^15 - 1 to -2^15, i.e from

32,767 to -32,768. Hope that helps