BAT32G1x9 user manual | Chapter 22 CAN control
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Rev.1.02
Note 1
Set the ABTCLR bit to 1 and the ABTTRG bit to 0 to resume ABT operation at buffer
number 0. If the ABTCLR bit is set to 1 and the ABTTRG bit is set to 1, subsequent
operations are not guaranteed. .
2.
If the automatic block transfer engine is cleared by setting the ABTCLR bit to 1, the
ABTCLR bit is automatically cleared after the processing of the purge request is complete.
3.
Do not set the ABTTRG bit in initialization mode. If the ABTTRG bit is set in initialization
mode, correct operation is not guaranteed after the mode changes from initialization mode
to ABT mode.
4.
Do not set the TRQ bit of the ABT packet buffer to 1 by the software in normal operation
mode of ABT. Otherwise, the operation is not guaranteed.
5.
The CnGMABTD register is used to set the insertion delay time between the completion of
the previous ABT packet and the TRQ bit set for the next ABT packet, and transmits
continuously in ABT mode when the transmission request is set in ABT message number
order. The time at which the message is actually transmitted to the CAN bus varies
depending on the state of transmission from other sites and the setting state of the packet
sending request other than the ABT message (packet buffer 8 to 15).
6.
If a transmission request is made for a message other than an ABT message, and a delay
time is not inserted in the time interval for the ABT transmission request (CnGMABTD =
00H) is automatically set, the message other than the ABT message may not depend on the
priority of the ABT message.
7.
When ABTTRG =1, do not clear the RDY bit to 0.
8.
If a packet is received from another node while the normal mode of operation with ABT is
active, the TX packet in the ABT region may be transmitted with a delay of one frame,
although the CnGMABTD register is set to 00H.
Note m=0
to
15
22.10.4
Transfer abort processing
(1) Transfers outside of Automatic Block Transfer (ABT) are aborted in normal operating mode
The user can abort the transmission request by clearing the TRQ bit of the CnMCTRLm register to 0,
and if the abort is successful, the TRQ bit will be cleared immediately. The TSTAT bit of the CnCTRL
register indicating the status of the CAN bus transmission and the CnTGPT register can be used to
check whether the transfer was successfully aborted (for more information, see Processing in Figure
(2) ABT transmissions are accompanied by transfer abort processing outside of automatic block transfers in normal
operating mode
The user can clear the ABTTRG bit of the CnGMABT register to 0 to abort the transfer request. After
checking the ABTTRG bit of the CnGMABT register = 0, clear the TRQ bit of the CnMCTRLm register
to 0. If the abort is successful, the TRQ bit is cleared immediately. The TSTAT bits of the CnCTRL
registers indicating the transfer status on the CAN bus and the CnTGPT register can be checked for
successful abortation (for details, see Processing in Figure 22-72).