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Chapter 19
CAN Controller (CAN)
Preliminary User’s Manual U17566EE1V2UM00
Figure 19-26
Setting transmission request (TRQ) to transmit message buffer after
redefinition
Caution
1.
When a message is received, reception filtering is performed in accordance
with the ID and mask set to each receive message buffer. If the procedure in
Figure 19-37 on page 748
is not observed, the contents of the message
buffer after it has been redefined may contradict the result of reception
(result of reception filtering). If this happens, check that the ID and IDE
received first and stored in the message buffer following redefinition are
those stored after the message buffer has been redefined. If no ID and IDE
are stored after redefinition, redefine the message buffer again.
2.
When a message is transmitted, the transmission priority is checked in
accordance with the ID, IDE, and RTR bits set to each transmit message
buffer to which a transmission request was set. The transmit message buffer
having the highest priority is selected for transmission. If the procedure in
Figure 19-26 on page 712
is not observed, a message with an ID not having
the highest priority may be transmitted after redefinition.
Exec
u
te
tr
a
n
s
mi
ss
ion?
W
a
it for 1
b
it of CAN d
a
t
a
.
S
et TRQ
b
it
S
et TRQ
b
it = 1
Cle
a
r TRQ
b
it = 0
Ye
s
No
Redefinition completed
END
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