University of California, Santa Barbara
Parity checking comprises a low-redundancy method for the design of reliable digital systems. While quite effective for detecting single-bit transmission or storage errors, parity encoding has not been widely used for checking the correctness of arithmetic results because parity is not preserved during arithmetic operations and parity prediction requires fairly complex circuits in most cases. The authors propose a general strategy for designing parity-checked arithmetic circuits that takes advantage of redundant intermediate representations. Because redundancy is often used for high performance anyway, the incremental cost of their proposed method is quite small.