Arduino Verkstad AB, the Swedish branch of Arduino, has developed a prototype that demonstrates a smart transducer network with a self-configurable communication protocol. The protocol is called I2C+, since it is based upon I2C. One of the possible areas of application is the EU funded PELARS project, where Arduino Verkstad is responsible for creating educational tools. Within the PELARS project, a maximum number of transducer modules is expected to be 20 modules, connected at the same time. The aim of this thesis was to create a testing tool and a test suite for the prototype system, which later could be used and also further developed by engineers at Arduino Verkstad, during the development of the final product. Though the testing tool was primarily needed for this particular system, it was considered desirable if it could be reused for similar projects as well. It was relevant to create the testing tool and the test suite in order to analyse the validity of the I2C+ protocol, which might become Arduino's future standard in connectivity between smart transducers. The performance of the I2C+ protocol also affects the implementation of the smart transducer system within the PELARS project. This work has been guided by a specification of requirements and also by a systematic top-down approach of solving several subproblems. A testing tool and a test suite was created, which serves as a proof-of-concept. The testing tool has a modular design, which makes the solution reusable for other purposes. The testing tool and the test suite was validated by using Arduino's prototype as a test object. Although only 10 transducer modules was used during these tests, the results showed that the prototype does not perform well for a growing number of modules. Therefore, improvement of the system and further testing is advised.