UPD78F0838 Renesas Electronics Corporation., UPD78F0838 Datasheet - Page 604

• Manufacturer Part Number: UPD78F0838
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

Cautions 1. When a message is received, reception filtering is performed in accordance with the ID and mask
15.8.4 Transition from initialization mode to operation mode
602
The CAN module can be switched to the following operation modes.
- Normal operation mode
- Normal operation mode with ABT
- Receive-only mode
- Single-shot mode
- Self-test mode
Figure 15-27. Setting Transmission Request (TRQ) to Transmit Message Buffer After Redefining
2. When a message is transmitted, the transmission priority is checked in accordance with the ID,
set to each receive message buffer.
Redefinition 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.
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 15-41. Message Buffer Redefinition during Transmission 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.
Preliminary User’s Manual U19748EJ1V0UD
CHAPTER 15 CAN CONTROLLER
Execute transmission?
Redefinition completed
Clear TRQ = 0
Set TRQ = 1
Set TRQ bit
End
Yes
If the procedure in Figure 15-40.
No
Message Buffer