SH7201 Datasheet, PDF (886/1196 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series

Section 19 Controller Area Network (RCAN-ET)
• Normal Mode
RCAN-ET operates in the normal mode.
• Listen-Only Mode:
ISO-11898 requires this mode for baud rate detection. The Error Counters are cleared and
disabled so that the TEC/REC does not increase the values, and the CTx Output is disabled so
that RCAN-ET does not generate error frames or acknowledgment bits. IRR13 is set when a
message error occurs.
• Self Test Mode 1
RCAN-ET generates its own Acknowledge bit, and can store its own messages into a reception
mailbox (if required). The CRx/CTx pins must be connected to the CAN bus.
• Self Test Mode 2
RCAN-ET generates its own Acknowledge bit, and can store its own messages into a reception
mailbox (if required). The CRx/CTx pins do not need to be connected to the CAN bus or any
external devices, as the internal CTx is looped back to the internal CRx. CTx pin outputs only
recessive bits and CRx pin is disabled.
• Write Error Counter
TEC/REC can be written in this mode. RCAN-ET can be forced to become an Error Passive
mode by writing a value greater than 127 into the Error Counters. The value written into TEC
is used to write into REC, so only the same value can be set to these registers. Similarly,
RCAN-ET can be forced to become an Error Warning by writing a value greater than 95 into
them.
• Error Passive mode
RCAN-ET needs to be in Halt Mode when writing into TEC/REC (MCR1 must be "1" when
writing to the Error Counter). Furthermore this test mode needs to be exited prior to leaving
Halt mode.Error Passive Mode: RCAN-ET can be forced to enter Error Passive mode.
Note:
the REC will not be modified by implementing this Mode. However, once running in
Error Passive Mode, the REC will increase normally should errors be received. In this
Mode, RCAN-ET will enter BusOff if TEC reaches 256 (Dec). However when this mode
is used RCAN-ET will not be able to become Error Active. Consequently, at the end of the
Bus Off recovery sequence, RCAN-ET will move to Error Passive and not to Error Active
When message error occurs, IRR13 is set in all test modes.
Rev. 2.00 Sep. 07, 2007 Page 858 of 1164
REJ09B0321-0200