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ARM has developed a new processor core specifically for safety applications in autonomous vehicles of all kinds (writes Nick Flaherty). The Cortex-A78AE adds new features compared with the current A76AE to allow engineers to balance the safety level of a design, starting out with bounded applications such as driverless shuttles and last-mile delivery robots, and then for the next generation of driverless cars built around Nvidia’s Orin processing platform. The design increases the core performance by 30% over the A76AE, and adds a hybrid mode where different cores can either run in lock-step for the highest ASIL-D safety level or separately for ASIL-B with additional diagnostics. This ‘split lock’ works on a cluster of four A76AE cores. In lock mode, pairs of cores run in lock-step, cross-checking in hardware on the same operation. This is used for the ASIL-D certification. For ASIL-B safety in split mode, the cores can be periodically taken offline for diagnostic testing to make sure they are operating correctly. In the previous version, all the cores had to stop when that happened. Another piece of hardware, the shared cluster manager (DSU- AE), now enables one core to always operate while the others are tested. The DSU-AE runs in locked mode, so there’s always one or more cores available in split mode, and the choice of split or locked mode for each core can be chosen at boot time to give developers flexibility. Multiple clusters can be grouped together in a chip to provide more processing power. This capability has been included in the latest version of the Arm Development Studio, which includes the Arm Compiler for Safety qualified by TUV SUD for use at the highest safety integrity levels. The core also specifically supports the ISO 26262 development process. Safety first for new ARM processor Driverless vehicles The Cortex-A76AE boosts core performance by 30% over the current version and allows the safety level of a vehicle design to be balanced