## 1 Introduction  
Wireless Sensors and Actuators Networks (WSANs) is an established and challenging technology, with a great potential impact on the measurement, communication and control applications to a variety of activities of the modern postindustrial society. According to market analyses, WSAN node sales will constitute a multi-trillion market in the next few years [1, 2]. Given the fact, during the last 25 years, the agricultural production sector has been transformed from a traditional labor-intensive sector into a technology-intensive one, it has been strongly considered as a very prosperous potential area for WSAN technology use. Indeed, a vast range of existing and future WSAN applications in agriculture have been identified and reported by many researchers [3, 4, 5]. Moreover, relatively-new terms have been introduced in current terminology, in order to express the trends in modern agriculture, such as: precision agriculture; precision farming; variable-rate management; etc. On the other hand,the majority of WSA deployments in agriculture are taking place on a short-scale research and development basis, rather than on a large-scale commercial solutions basis. The massive expansion of WSAN technology in agriculture appears to lag behind the market's expectations. Many researchers have reported certain technological causes for this, which relate to hardware design issues, such as standardization in protocols and development tools, configurability, expandability, scalability in computing power, and memory capacity [3; 6; 7; 8; 9]. Examining the idiosyncrasy of the real-world (real-life) WSAN applications, the most common critical features found are: the operation in the real environmental and spatiotemporal conditions (far away from the lab), the systems are on the end-users hands, the energy autonomy, the need for long-term serviceability and management, the maintainability, the expandability, the reconfigurability, the reusability, the robustness and ruggedness, the long-standing reliability and the low cost per WSAN node [10]. Therefore, any single factor, which can negatively affect one or more of the aforementioned features, could jeopardize the success of the whole WSAN implementation. Regarding agriculture, these features have greater impact to the success of WSAN applications, because, traditionally, this sector requires scalable wireless networks comprised by large number of nodes covering huge physical remote areas, capable of measuring a variety of physical parameters [11]. Furthermore, very often, the harsh operating environment has been reported, by many experts, as a major source of implementation problems [12; 13]. Extreme temperatures, humidity, rain, snow, wind, and sunlight radiation, can all seriously threat the normal operation of WSAN hardware systems, which, in their vast majority, have been designed for indoor environments (labs, offices, etc.) [6; 9; 14; 15; 16]. Unfortunately, the physical agricultural environment cannot successfully be modeled and tested by simulation methods (e.g., [17]). For example, the behavior of real batteries [18; 19] or the radio signal propagation [20; 21] are typical cases of operation parameters that are extremely difficult to model and fully simulate, so the design of hardware WSAN systems for the agricultural domain is more complicated than in other application domains. Since the early days of the WSAN technology up to today, nodes' hardware architecture was solely governed according to the block diagram depicted in Figure 1[22; 23]. It is a microcontroller-based system with all the necessary circuitry for sensors, and actuators, equipped with a radio frequency transceiver for data communication and networking. Even recent research attempts to use field-programmable gate arrays (FPGAs), instead of microcontroller units (MCUs), in WSAN nodes are based to the traditional architecture [24; 25].