upd70f3422gj-gae-qs-ax Renesas Electronics Corporation., upd70f3422gj-gae-qs-ax Datasheet - Page 712

• Manufacturer Part Number: upd70f3422gj-gae-qs-ax
• Description: 32-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

Chapter 19
712
Figure 19-26
Caution
Setting transmission request (TRQ) to transmit message buffer after
redefinition
1.
2.
Preliminary User’s Manual U17566EE1V2UM00
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.
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.
Wait for 1 bit of CAN data.
Redefinition completed
Clear TRQ bit = 0
Set TRQ bit = 1
transmission?
Set TRQ bit
Execute
END
Yes
No
CAN Controller (CAN)