XC161 Datasheet, PDF (263/419 Pages) Infineon Technologies AG – 16-Bit Single-Chip Microcontroller with C166SV2 Core Volume 2 (of 2): Peripheral Units

XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
TwinCAN Module
21.1.4.5 Single Data Transfer Mode
The single data transfer mode is a useful feature in order to broadcast data over the CAN
bus without unintended doubling of information. The single data transfer mode is
selected via bit SDT in the FIFO/Gateway control register MSGFGCRn.
Each received data frame with matching identifier is automatically stored in the
corresponding receive message object if MSGVAL is set to ‘10’. When data frames
addressing the same message object are received within a short time interval,
information might get lost (indicated by MSGLST = ‘10’), if the CPU has not processed
the former message object contents in time.
Each arriving remote frame with matching identifier is answered by a data frame based
on the contents of the corresponding message object. This behavior may lead to multiple
generation and transmission of identical data frames according to the number of
accepted remote requests.
If SDT is set to ‘1’, the CAN node controller automatically resets bit MSGVAL in a
message object after receiving a data frame with corresponding identifier. All following
data frames, addressing the disabled message object, are ignored until MSGVAL is set
again by the CPU.
If SDT is set to ‘1’, the CAN node controller automatically resets bit MSGVAL in the
addressed message object, when the transmission of the corresponding data frame has
been finished successfully. In consequence, all following remote requests concerning
the disabled message object are ignored until MSGVAL is set again by the CPU. This
feature allows for transmitting data in a consecutive manner without unintended doubling
of any information.
If SDT is cleared, control bitfield MSGVAL is not reset by the CAN node controller.
User’s Manual
TwinCAN_X1, V2.1
21-23
V2.2, 2004-01