The GRCAN core is a CAN controller with an AHB DMA backend. The APB bus is used for configuration, control and status handling and the AHB bus is used for retrieving and storing CAN messages in memory external to the CAN controller. GRCAN supports transmission and reception of sets of messages by use of circular buffers located in memory external to the core. Separate transmit and receive buffers are assumed. Reception and transmission of sets of messages can be ongoing simultaneously.