Bit-flip coding

A memory system employing bit flip coding comprising:

• a bit-flip encoder to receive an input data and to place information bits of the input data into a binary array, the bit-flip encoder to encode the binary array having n rows and n columns by flipping bits in a redundancy-intersecting vector of the binary array until Hamming weights of the rows and columns of the binary array are within a predetermined range Δ of n divided by two, the binary array comprising an n-bit redundancy vector and n squared minus n information bits, the information bits being stored in array locations of the binary array outside of the n-bit redundancy vector;
• a resistive crossbar memory to receive and store the binary array encoded by the bit-flip encoder;
• and
• a decoder to retrieve a selected encoded bit of the stored, encoded binary array from the resistive crossbar memory, and to decode the selected encoded bit using a corresponding encoded bit of the n-bit redundancy vector.

A method comprising:

• receiving an input data to write to a memory;
• mapping the input data into a binary array stored in non-transitory computer memory, the binary array having n rows and n columns, the input data having n squared minus n information bits;
• bit-flip encoding the binary array comprising flipping bits in a redundancy-intersecting vector of the binary array using a processor until Hamming weights of the rows and the columns of the binary array are within a predetermined range Δ of n divided by two, wherein the mapping of the input data places the information bits in locations in the binary array that are not occupied by n redundancy bits of a redundancy vector stored in the binary array, writing the bit-flip encoded binary array to the memory;
• storing the encoded binary array in an n×n crossbar array of resistive memory elements, wherein storing comprises writing to a selected resistive memory element of the n×n crossbar array, the writing comprising selecting and driving a row line and a column line of the n×n crossbar array connected to the selected resistive memory element, wherein all unselected row lines and column lines of the n×n crossbar array are floating during the writing;
• and retrieving a selected encoded bit of the bit-flip encoded binary array from the memory, and decoding, using a decoder, the selected encoded bit.