Controller with flexible data-rate targets autonomous cars
Standalone controller for the Controller Area Network, (CAN), the DCAN FD is widely used in automotive and industrial applications. It conforms to Bosch CAN 2.0B specification (2.0B Active) and CAN FD (Flexible Data-rate) - in accordance to ISO 11898-1:2015.
Standard CAN requirements become insufficient in modern automotive. The carmakers demand more bandwidth and more throughputs for most CAN-based in-vehicle networks. The DCAN FD IP Core is also a suitable alternative for non-automotive projects where not the increasing speed is the target. The longer payload (more than eight byte) becomes crucial then.
The improved protocol overcomes standard CAN limits: data can be transmitted faster than with 1Mbps (even up to 8Mbps) and the payload (data field) is up to 64 byte long. When only one node is transmitting, the bit-rate can be increased, because no nodes need to be synchronised. Of course, before the transmission of the ACK slot bit, the nodes need to be re-synchronised.
The core has a simple CPU interface (8/16/32 bit configurable data width), with small or big endian addressing scheme, explained Tomasz Krzyzak, VCEO in Digital Core Design. “Hardware message filtering and 128 byte receive FIFO enable back-to-back message reception, with minimum CPU load. The DCAN FD is described at RTL level, allowing target use in FPGA or ASIC technologies.”