SH7058 Datasheet, PDF (638/1130 Pages) Renesas Technology Corp – Renesas SuperHTM RISC engine

16.7 Operation
16.7.1 Test Mode Settings
The HCAN has various test modes. Bits TST[7:0] (bits 15 to 8 in MCR) are used to select the
HCAN-II test mode. The initial settings allow the HCAN to operate in normal mode. The
following table is examples for test modes.
Table 16.8 Test Modes
Bit15: Bit14: Bit13: Bit12: Bit11: Bit10: Bit9: Bit8:
TST7 TST6 TST5 TST4 TST3 TST2 TST1 TST0 Description
0
0
0
0
0
0
0
0
Normal mode (initial value)
1
0
0
0
1
0
1
0
Listen-only mode (receive-only)
1
0
0
1
0
0
0
0
Self test mode 1 (external)
1
0
0
1
0
1
1
1
Self test mode 2 (internal)
1
1
0
0
0
0
0
0
Error passive mode 1
1
0
1
0
0
0
0
0
Error passive mode 2
Normal Mode: The HCAN operates normally.
Listen-Only Mode: The ISO-11898 requires this mode for baud rate detection etc. The error
counters are disabled so that TEC/REC does not increment the values, and the Tx output is
disabled so that the HCAN does not generate error frames.
Self Test Mode 1: The HCAN generates its own acknowledge bit. The Rx and Tx pins must be
connected to the CAN bus.
Self Test Mode 2: The HCAN generates its own acknowledge bit. The Rx and Tx pins do not
need to be connected to the CAN bus or any external devices, as the internal Tx is looped back to
be connected to the internal Rx.
Important: In self test modes 1 and 2, the transmitted data is not received in the internal mailbox.
Error Passive Mode 1: The HCAN can be forced to become an error passive node by writing a
value (greater than 127) to the error counter. (MCR1 must be 1 when writing to the error counter).
The value written to TEC is used to write to REC, so only the same value can be set to these
registers. Also, the HCAN needs to be in halt mode when writing to TEC/REC.
Error Passive Mode 2: The HCAN can be forced to become an error passive node by setting
TST5.
Rev. 3.0, 09/04, page 597 of 1086