Cyclone® V Hard Processor System Technical Reference Manual

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

26.3.5.1. Silent Mode

The CAN controller is set in the silent mode by programming the silent mode (Silent) bit in the test register (CTR) to 1. In silent mode, the CAN controller is able to receive valid data frames and valid remote frames, but it holds the CAN_TXD pin high, sending no data to the CAN bus. The silent mode can be used to analyze the traffic on a CAN bus without affecting it by the transmission of dominant bits (acknowledge bits, error frames). In ISO 11898-1, the silent mode is called the bus monitoring mode.

Figure 137. CAN Core in Silent Mode