Cyclone® V Hard Processor System Technical Reference Manual

ID 683126
Date 8/28/2023
Public
Document Table of Contents

26.3.5.2. Loopback Mode

The CAN controller is set in loopback mode by programming the loopback mode (LBack) bit in the test register (CTR) to 1. In loopback mode, the CAN controller treats its own transmitted messages as received messages and stores them (if they pass acceptance filtering) to a receive buffer.

To be independent from external stimulation, the CAN controller ignores acknowledge errors in loopback mode. In this mode, the CAN controller provides internal feedback from its transmit (TX) output to its receive (RX) input. The actual value of the input pin is disregarded by the CAN controller.

Figure 138. CAN Core in Loopback Mode