NEC V850ES/F 3-L Series User Manual page 613

CAN Controller (CAN)
Caution
Transmit history list (THL)
7
6
5
4
Last out- Message buffer 7
3
message
Message buffer 2
2
pointer
Message buffer 9
1
(LOPT)
Message buffer 6
0
Transmit history list (THL)
Message buffer 5
7
Message buffer 8
6
Message buffer 4
5
Message buffer 3
4
Message buffer 7
3
2
Last out- Message buffer 10
1
message
Message buffer 6
0
pointer
(LOPT)
TOVF = 1
LOPT is blocked
TOVF = 1 denotes that LOPT equals TGPT - 1 while message buffer number stored to element indicated by LOPT - 1.
Figure 18-31
If the history list is in the overflow condition (TOVF is set), reading the history
list contents is still possible, until the history list is empty (indicated by THPM
flag set). Nevertheless, the history list remains in the overflow condition, until
TOVF is cleared by software. If TOVF is not cleared, the THPM flag will also
not be updated (cleared) upon successful transmission of a new message.
This may lead to the situation, that THPM indicates an empty history list,
although a successful transmission has taken place, while the history list is in
the overflow state (TOVF and THPM are set).
Event:
- CPU confirms Tx completion
of message buffer 6, 9, and 2.
- Tx completion of message
buffer 3, and 4.
Transmit
history list
get pointer
(TGPT)
Event:
- Message buffer11, 13, and 14
completes transmission.
- Overflow situation occurs.
Transmit
history list
get pointer
(TGPT)
Transmit history list
User's Manual U18743EE1V2UM00
Transmit history list (THL)
7
6
Message buffer 4
5
Message buffer 3
4
Last out- Message buffer 7
3
message
2
pointer
1
(LOPT)
0
Event:
- Message buffer 8, 5, 6, and 10 completes transmission.
- THL is full.
- TOVF is set.
Transmit history list (THL)
Message buffer 5
7
Message buffer 8
6
Message buffer 4
5
Message buffer 3
4
Message buffer 7
3
2
Last out- Message buffer 14
1
message
Message buffer 6
0
pointer
(LOPT)
TOVF = 1
LOPT is blocked
Chapter 18
Transmit
history list
get
pointer
(TGPT)
Transmit
history list
get
pointer
(TGPT)
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