The computing and communication architecture of the DLR Hand Arm System is presented. Its task is to operate the robot's 52 motors and 430 sensors. Despite that complexity, the main design goal for it is to create a flexible architecture that enables high-performance feedback control with cycles beyond 1kHz. Flexibility is achieved through a hierarchical net of computing nodes that goes from commercial-of-the-shelf hosts down to the physical interfaces of sensors and actuators. The concept of a Hardware Abstraction Layer (HAL) provides a convenient high-level interface to the entire robotic hardware. First experiments with prototypical control applications, featuring 100 kHz and 3 kHz control loops, demonstrate the performance of the architecture.