AP29002
Standalone TwinCAN Controller
Product Overview
Application Note
4
V 1.0, 2004-02
1
Product Overview
The TwinCAN module in the 82C900 permits the connection and autonomous handling
of two independent CAN buses. It supports the maximum CAN baud rate of 1M baud
and complies with CAN protocol version 2.0B (active).
The full-CAN module has 32 message objects, which can be independently assigned
to one of the two buses. The scalable FIFO mechanism for reception and transmission
greatly improves the real-time behavior of the system. The device provides built-in
automatic gateway functionality for data exchange between both CAN buses,
minimizing the CPU's message handling load. The gateway feature can also be used
for automatic reply to received messages.
The powerful interrupt structure permits application-specific interrupt generation. The
enhanced acceptance filtering dedicates one acceptance mask to each message
object. In addition, a 16-bit frame count/time-stamp is implemented for each message
object. The 82C900's analyzing mode, during which no dominant bits are sent, makes
it ideal for diagnostic applications.
Figure 1
82C900 Architectural Overview
