Datasheet

V850ES/JG3-H, V850ES/JH3-H CHAPTER 20 CAN CONTROLLER

R01UH0042EJ0500 Rev.5.00 Page 1003 of 1513

Aug 12, 2011

20.13 Diagnosis Functions and Special Operational Modes

The CAN module provides a receive-only mode, single-shot mode, and self-test mode to support CAN bus diagnosis

functions or the operation of special CAN communication methods.

20.13.1 Receive-only mode

The receive-only mode is used to monitor receive messages without causing any interference on the CAN bus and can

be used for CAN bus analysis nodes.

For example, this mode can be used for automatic baud-rate detection. The baud rate in the CAN module is changed

until “valid reception” is detected, so that the baud rates in the module match (“valid reception” means a message frame

has been received in the CAN protocol layer without occurrence of an error and with an appropriate ACK between nodes

connected to the CAN bus). A valid reception does not require message frames to be stored in a receive message buffer

(data frames) or transmit message buffer (remote frames). The event of valid reception is indicated by setting the

C0CTRL.VALID bit (1).

Figure 20-33. CAN Module Terminal Connection in Receive-Only Mode

CAN macro

CRXD0CTXD0

Fixed to the

recessive level