RL78/D1A User's Manual: Hardware - Renesas

Under development
Preliminary document
Specifications in this document are tentative and subject to change.
RL78/D1A CHAPTER 14 CAN CONTROLLER
(22) CAN message configuration register (C0MCONFm, C1MCONFm)
The C0MCONFm, C1MCONFm register is used to specify the type of the message buffer and to set a mask.
Figure 14-48. Format of CAN Message Configuration Register (C0MCONFm, C1MCONFm) (1/2)
Address: See Table 14-16 After reset: Undefined R/W
C0MCONFm,
C1MCONFm
7 6 5 4 3 2 1 0
OWS RTR MT2 MT1 MT0 0 0 MA0
OWS Overwrite Control Bit
0 The message buffer that has already received a data frame Note is not overwritten by a newly
received data frame. The newly received data frame is discarded.
1 The message buffer that has already received a data frame Note is overwritten by a newly received
data frame.
Note The “message buffer that has already received a data frame” is a receive message buffer whose DN
bit has been set to 1.
Remark A remote frame is received and stored, regardless of the setting of OWS bit and DN
bit. A remote frame that satisfies the other conditions (ID matches, RTR = 0, TRQ = 0)
is always received and stored in the corresponding message buffer (interrupt
generated, DN flag set, MDLC [3:0] bits updated, and recorded to the receive history
list).
RTR Remote Frame Request Bit Note
0 Transmit a data frame.
1 Transmit a remote frame.
Note The RTR bit specifies the type of message frame that is transmitted from a message
buffer defined as a transmit message buffer. Even if a valid remote frame has been
received, RTR of the transmit message buffer that has received the frame remains
cleared to 0. Even if a remote frame whose ID matches has been received from the CAN
bus with the RTR bit of the transmit message buffer set to 1 to transmit a remote frame,
that remote frame is not received or stored (interrupt generated, DN flag set, MDLC [3:0]
bits updated, and recorded to the receive history list).
MT2 MT1 MT0 Message Buffer Type Setting Bit
0 0 0 Transmit message buffer
0 0 1 Receive message buffer (no mask setting)
0 1 0 Receive message buffer (mask 1 set)
0 1 1 Receive message buffer (mask 2 set)
1 0 0 Receive message buffer (mask 3 set)
1 0 1 Receive message buffer (mask 4 set)
Other than above Setting prohibited
Remark m = 0 to 15
R01UH0317EJ0004 Rev. 0.04 875
Feb. 22, 2013