TWK-ELEKTRONIK GmbH: Updating with bootloader function

A new bootloader functionality has been developed to adapt the complex software implemented in the absolute encoders and inclinometers to the latest status. This enables the user to reprogramme existing devices which are already in operation on-site. To do this, a new programme code (hex file) is implemented using a PC with a CANopen interface, which acts as the master.

The UDS protocol (Unified Diagnostic Service) according to the ISO 14229-1 standards is used for updating. UDS is an automotive electronics communications protocol. The UDS protocol arose from ISO 14230-3 (KWP2000), ISO 15765-3 (diagnostics on CAN) and the GMLAN specifications from General Motors (ISO 15765-2). Via the 0x1023 – OS command object, the CANopen subscriber is able to respond to UDS messages and therefore to enable operating programme downloading.

The bootloader of the CAN controller in the absolute encoder transfers the new programme code to the flash memory. The bootloader programme is password-protected, with the result that access is only available to authorised users. This new, extended functionality enables the user to carry out software changes relatively easily on the existing hardware platform, whether for error rectification purposes or to extend the functional scope.