The checksum was the sum of all bytes in the packet modulo 256. The modulo operation was easily computed by discarding all but the eight least significant bits of the result, or alternatively on an eight-bit machine, ignoring arithmetic overflow which would produce the same effect automatically. In this way, the checksum was restricted to an eight-bit quantity. For example, if this checksum method was used on a tiny data packet containing only two bytes carrying the values 130 and 130, the total of these codes is 260 and the resulting checksum is 4.