Originally Posted by jasonver2.0
checksum+=long(buf+i*4) - i dont know whats happening here
Say 'i' contains 3 .. then you would get the value from location of 'buf' + 12 (cast to long) and add it to 'checksum' (also defined as long).
buf : 444F5300 'D' 'O' 'S'
so checksum would be checksum plus 43FA003E.