The Budapest University of Technology and Economics is participant of an international competition series called Formula Student since 2007. The competing team’s name is BME-FRT (Formula Racing Team). The main objective of the contest is to design and build a racing car. The team will be the part of the field in 2010 as well, and plans a lot of development on the newly built car. The overall redesignment of the car’s electronic system takes place among these developments, the target is to create the possibility of a general automotive diagnosis.
The microcontrollers that provide electronic functions are nearly inaccessible after deploying them into the car. Therefore if there’s some malfunction in the software, the correction of the problem is very circumstantial, and the reprogramming of microcontrollers is needed. This can be carried out by using the JTAG or UART communication ports of the device that are designed for this express purpose. To do so, the controllers have to be disassembled from their place, but this is what we want to avoid. That’s why it is required to allow software update via one of the controller’s permanently used communication ports, namely the CAN (Controller Area Network) port. This function is achieved by a program called bootloader, which runs on the microcontroller. The thesis contains the development of such a CAN-bootloader that is able to perform this functionality, and, in addition, allows best-effort guarantee of all time reliability with realization of basic intelligent behavior.
For this purpose the CAN communication usually performed in a standardized way. While we are encroaching in the functioning of the controller, it is practical to merge this task with the calibration and diagnosis of the devices, which is determined by a particular protocol. The CAN Calibration Protocol (CCP) had been designed for such challenges and it is frequently used in automotive electronics.
Using this protocol it is achievable to analyze the microcontrollers, based on comprehensive diagnostic measurements. For this analysis, a PC-based application is needed, which is able to carry out communication determined by the CAN Calibration Protocol.
The making of this software’s basis is a part of the thesis. This implies creating the possibility to fulfill diagnostic functions that are common to all controllers – including the reprogramming method via CAN network.