The design and test of a smartcard chip using a CHAIN self-timed network-on-chip

The CHAIN self-timed network-on-chip (NoC) architecture provides a flexible, clock-independent solution to the problems of system-on-chip (SoC) interconnect. In this paper we look at the use of CHAIN in a low-performance, smartcard chip to connect two self-timed processors and a range of memories and peripherals. Key design-time advantages provided by the use of CHAIN in this design included the ability to operate a very-narrow, high-frequency network fabric using serial communication without the need for high frequency clocking, rapid assembly in the final stages of the design and the avoidance of the need to perform timing analysis or validation on the SoC interconnect. Additionally we describe a bare port that provided direct access to the CHAIN fabric which was instrumental in testing and debugging the smartcard chip.