A novel spatio-temporal adaptive bus encoding for reducing crosstalk interferences with trade-offs between performance and reliability

Due to advanced process technologies the decreasing distance between wires has led to significant bus interferences that introduce crosstalk delay and noise. We first propose two encoding schemes, namely DUCE and GASIE, that can reduce crosstalk delay and noise on the bus lines. The DUCE scheme is a temporal encoding so it needs no additional bits to implement. It can be easily used in existing systems without additional modification in the hardware architecture. For improving performance, we propose a spatial encoding scheme called GASIE which has shielding lines protection and additional bits for transmitting control signals. Compared to existing spatial encoding methods, GASIE not only does not need any profiling information, but also achieves better results. Finally, we combine DUCE and GASIE into a novel spatio-temporal adaptive encoding (STAE) to tradeoff between performance and reliability. The experimental results for various applications showed significant reductions in the number of patterns that were most likely to produce crosstalk delay and errors. The two adjacent transitions and the aggressors can be completely eliminated in the DUCE scheme. While the GASIE scheme can achieve up to 59.9% average reduction of two aggressors, the STAE scheme gives a strongly error tolerant environment of 70% reduction in aggressors and adjacent transitions at the cost of 10% performance loss.