
XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
TwinCAN Module
User’s Manual
21-17
V2.2, 2004-01
TwinCAN_X1, V2.1
21.1.4.2
Handling of Remote and Data Frames
Message objects can be set up for transmit or receive operation according to the
selected value for control bit DIR. The impact of the message object type on the
associated CAN node controller concerning the generation or reception of remote and
data frames is illustrated in
.
Table 21-1
Handling of Remote and Data Frames
A transmission
request (TXRQ =
‘10’) for this
message object
generates …
If a data frame with
matching identifier
is received …
If a remote frame
with matching
identifier is
received …
Receive Object
(receives data
frames, transmits
remote frames,
control bit DIR = ‘0’)
… a remote frame.
The requested data
frame is stored in
this message object
on reception.
… the data frame is
stored in this
message object.
… the remote frame
is NOT taken into
account.
Transmit Object
(transmits data
frames, receives
remote frames,
control bit DIR = ‘1’)
… a data frame
based upon the
information stored in
this message
object.
… the data frame is
NOT stored.
… the remote frame
is stored in this
message object and
RMTPND and
TXRQ are set to
‘10’.
A data frame, based
upon the
information stored in
this message
object, is
automatically
generated if
CPUUPD is set to
‘01’.