5.12.1 Controller Area Network (CAN)
The CAN module uses the IP known as DCAN. This document uses the names CAN and DCAN interchangeably to reference this peripheral.
The CAN module implements the following features:
- Complies with ISO11898-1 (Bosch® CAN protocol specification 2.0 A and B)
- Bit rates up to 1 Mbps
- Multiple clock sources
- 32 message objects (mailboxes), each with the following properties:
- Configurable as receive or transmit
- Configurable with standard (11-bit) or extended (29-bit) identifier
- Supports programmable identifier receive mask
- Supports data and remote frames
- Holds 0 to 8 bytes of data
- Parity-checked configuration and data RAM
- Individual identifier mask for each message object
- Programmable FIFO mode for message objects
- Programmable loopback modes for self-test operation
- Suspend mode for debug support
- Software module reset
- Automatic bus on after bus-off state by a programmable 32-bit timer
- Two interrupt lines
- DMA support
For a CAN bit clock of 100 MHz, the smallest bit rate possible is 3.90625 kbps.
The accuracy of the on-chip zero-pin oscillator is in Table 5-22. Depending on parameters such as the CAN bit timing settings, bit rate, bus length, and propagation delay, the accuracy of this oscillator may not meet the requirements of the CAN protocol. In this situation, an external clock source must be used.
Figure 5-69 shows the CAN block diagram.
Figure 5-69 CAN Block Diagram