38.2.6.2 Idle Mode

The system can be set to run in a Low-Power mode, called Idle mode. When the device is in Idle mode, the CPU is disabled and only select peripherals are active. Based on the configuration of the CAN SIDL bit, the module can either be in or out of Idle mode:

• If SIDL = 0, the module continues operation in Idle mode. If the module generates an interrupt while in Idle mode, the interrupt may generate a wake-up event.

• If SIDL = 1, the module stops when the device is in Idle mode. The module performs the same procedures when stopped in Idle mode as it does in Disable mode and the same requirements apply.

The user needs to ensure that the module is not active when the CPU transitions to Idle mode with SIDL = 1. To protect the CAN bus system from fatal consequences due to violation of this rule, the module will drive the TX pin into the Recessive state while stopped in Idle mode. If the CAN SIDL bit is set, the recommended procedure is to bring the module into Disable mode before the device is placed in Idle mode.