Datasheet

V850ES/JG3-H, V850ES/JH3-H CHAPTER 20 CAN CONTROLLER
R01UH0042EJ0500 Rev.5.00 Page 975 of 1513
Aug 12, 2011
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TRQ Message buffer transmission request bit
0 No message frame transmitting request that is pending or being transmitted is in the message buffer.
1
The message buffer is holding transmission of a message frame pending or is transmitting a message
frame.
Caution Do not set the TRQ bit and RDY bit to 1 at the same time. Be sure to set the RDY bit to 1
before setting the TRQ bit to 1.
RDY Message buffer ready bit
0 The message buffer can be written by software. The CAN module cannot write to the message buffer.
1
Writing the message buffer by software is ignored (except a write access to the RDY, TRQ, DN, and MOW
bits). The CAN module can write to the message buffer.
Cautions 1. Do not clear the RDY bit (0) during message transmission. Follow transmission abort
procedures in order to clear the RDY bit for redefinition.
2. If the RDY bit is not cleared (0) even when the processing to clear it is executed, execute
the clearing processing again.
3. Confirm, by reading the RDY bit again, that the RDY bit has been cleared (0) before writing
data to the message buffer.
However, it is unnecessary to confirm that the TRQ or RDY bit has been set (1) or that the
DN or MOW bit has been cleared (0).
(b) Write
Clear MOW Setting of MOW bit
0 MOW bit is not changed.
1 MOW bit is cleared to 0.
Set IE Clear IE Setting of IE bit
0 1 IE bit is cleared to 0.
1 0 IE bit is set to 1.
Other than above IE bit is not changed.
Caution Be sure to set the IE and RDY bits separately.
Clear DN Setting of DN bit
1 DN bit is cleared to 0.
0 DN bit is not changed.
Caution Do not set the DN bit to 1 by software. Be sure to write 0 to bit 10.