Systems, methods and computer program products for providing a nested
two-bit symbol bus error correcting code. Methods include constructing a
nested error correcting code (ECC) scheme. The method includes receiving
a Hamming distance n code. A symbol correcting code H-matrix is created
by iteratively adding rows of H-matrix bits on a symbol column basis such
that the symbol correcting code H-matrix describes a symbol correcting
code, and the Hamming distance n code is preserved as a subset of the
symbol correcting code H-matrix.