Hand in hand with the inevitable increase in vehicle connectivity solutions, the high security and safety demands for automotive embedded systems are emphasizing the importance of thorough testing of newly developed software components. The high quality of the software is ensured through the usage of various tools at the development stage. This paper introduces an implementation of such a tool, which is based on a standard microcontroller platform and provides functionalities of a Rapid Prototyping System (RPS). The implementation is based on the universal calibration protocol XCP and utilization of an XCP-Master controller. The tool also acts as an intelligent watchdog, as it enables close behavioural monitoring of novel functionalities within an Electronic Control Unit (ECU). That makes the tool especially suitable for dependable AI testing in the scope of safetycritical applications. This is potentially a crucial building block of a safety net for testing of novel functionalities on a 'grey-box-like' ECU. Furthermore, the XCP-Master controller also provides the possibility to utilize the platform as an Ethernet-CAN message gateway for access to remote devices.