Function crc_sum_of_bytes

libraries/AP_Math/crc.cpp:659–662

sums the bytes in the supplied buffer, returns that sum mod 256 (i.e. shoved into a uint8_t)

// sums the bytes in the supplied buffer, returns that sum mod 256
// (i.e. shoved into a uint8_t)
uint8_t crc_sum_of_bytes(const uint8_t *data, uint16_t count)
{
    return crc_sum_of_bytes_16(data, count) & 0xFF;
}