Minimized and nearly deterministic end-to-end latency facilitates real-time data acquisition and actuator control. In addition, defined latency is an integral part of quality-oriented service in order to get closer to the reliability of wired networks and at the same time takes advantage of wireless networking. This article introduces a QoS routing protocol capable of balancing power consumption between wireless sensor and actuator nodes while minimizing end-to-end latency. We introduce a time-division multiple access scheme in the routed wireless network to enable defined latency, and in addition, it improves the energy efficiency by avoiding collisions, which eliminates time and energy consuming retries. Our novel routing method allows latency and round-trip times to be calculated in advance. We implement a demonstrator and show experimental results of a wireless sensor network with our proposed routing scheme.