Renesas M32R/ECU Series User Manual

13
13-80
32180 Group User’s Manual (Rev.1.0)
CAN MODULE
13.5 Transmitting Data Frames
(4) Completion of data frame transmission
When data frame transmission has finished, the CAN Message Slot Control Register’s TRFIN (Transmit/
Receive Finished) bit and the CAN Slot Interrupt Request Status Register are set to "1". Also, a timestamp
count value at which transmission has finished is written to the CAN Message Slot Timestamp (C0MSLnTSP,
C1MSLnTSP), and the transmit operation is thereby completed.
If the CAN slot interrupt request has been enabled, an interrupt request is generated at
completion of transmit operation. The slot which has had transmission completed goes to an
inactive state and remains inactive (neither transmit nor receive) until it is newly set in software.
B'1000 0010
B'0000 0001
(Note 1)
B'1000 0001
B'0000 0000
(Note 1)
B'1000 0000
Write H'80
Transmission aborted
Transmit request
accepted
Note 1: When in this state, data can be written to the message slot.
Transmission
aborted
Transmit request accepted
Transmission aborted
Transmission completed
Transmission aborted
Transmi
ssion completed
Wait for transmission
B'0000 0010
Lost in CAN bus arbitration
or a CAN bus error occurs
Lost in CAN bus arbitration or
a CAN bus error occurs
Figure 13.5.2 Operation of the CAN Message Slot Control Register during Data Frame Transmission
13.5.3 Transmit Abort Function
The transmit abort function is used to cancel a transmit request that has once been set. This is accomplished by
writing H’0F to the CAN Message Slot Control Register for the slot to be canceled. When transmit abort is
accepted, the CAN module clears the CAN Message Slot Control Register’s TRSTAT (Transmit/Receive Sta-
tus) bit to "0", allowing for data to be written to the message slot. The following shows the conditions under which
transmit abort is accepted.
[Conditions]
• When the target message is waiting for transmission
• When a CAN bus error occurs during transmission
• When lost in CAN bus arbitration
1 2 3 4 5 6 b7(b15)(b8)b0
RMRRTR RL RA ML TRSTAT TRFIN
00000000
Bit arrangement in the CAN Message Slot Control Register

Renesas M32R/ECU Series Specifications

General

Brand	Renesas
Model	M32R/ECU Series
Category	Computer Hardware
Language	English