Elliptic Curve Cryptography (ECC) based processors have gained large attention in the context of embedded-system design due to their ability of efficient implementation. In this paper, we present a low-resource processor that supports ECC operations for less than 9 kGEs. We base our design on an optimized 16-bit microcontroller that provides high flexibility and scalability for various applications. The design allows the use of an optimized RAM-macro block and reduces the complexity by sharing various resources of the controller and the datapath. Our results improves the state of the art in low-resource $\mathbb{F}_{2^{163}}$ ECC implementations (14% less area needed compared to the best solution reported). The total size of the processor is 8,958 GEs for a 0.13 μm CMOS technology and needs 285 kcycles for a point multiplication. It shows that the proposed solution is well suitable for low-power designs by providing a power consumption of only 3.2 μW at 100 kHz.