A method for data error checking includes accessing a plurality of sets of data, each of the sets of data having a plurality of bits; integrating the plurality of sets of data into integral data; generating error checking data according to the integral data, the error checking data being changed following any change of the plurality of sets of data; dividing the error checking data into a plurality of sets of sub-checking data, each set of sub-checking data corresponding to one of the plurality of sets of data; and when transmitting each of the plurality of sets of data in order, transmitting the corresponding sub-checking data in the meantime.