A companion chip for a microcontroller has a microprocessor bus domain and a peripheral module bus domain, which are connected to each other via a bus bridge. The microprocessor bus domain includes at least one microprocessor core, and the peripheral module bus domain includes at least one global time-management module as well as modules for communication with the outside world and for signal processing. The companion chip further includes at least one FIFO module for transmitting data within the chip, and between the chip and the microcontroller, and a management module connected to the FIFO module, which ensures the consistency of the data by associating a respective time value and/or an angle of rotation.