Datasheet

V850ES/JG3-H, V850ES/JH3-H CHAPTER 20 CAN CONTROLLER
R01UH0042EJ0500 Rev.5.00 Page 966 of 1513
Aug 12, 2011
(17) CAN0 module transmit history list register (C0TGPT)
The C0TGPT register is used to read the transmit history list.
(1/2)
After reset: xx02H R/W Address: 03FEC064H
(a) Read
15 14 13 12 11 10 9 8
C0TGPT TGPT7 TGPT6 TGPT5 TGPT4 TGPT3 TGPT2 TGPT1 TGPT0
7 6 5 4 3 2 1 0
0 0 0 0 0 0 THPM TOVF
(b) Write
15 14 13 12 11 10 9 8
C0TGPT 0 0 0 0 0 0 0 0
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0
Clear
TOVF
(a) Read
TGPT7 to TGPT0 Transmit history list read pointer
0 to 31
When the C0TGPT register is read, the contents of the element indexed by the read pointer
(TGPT) of the transmit history list are read. These contents indicate the number of the message
buffer to which a data frame or a remote frame was transmitted last.
THPM
Note 1
Transmit history pointer match
0 The transmit history list has at least one message buffer number that has not been read.
1 The transmit history list has no message buffer numbers that have not been read.
TOVF
Note 2
Transmit history list overflow bit
0
All the message buffer numbers that have not been read are preserved. All the numbers of the
message buffers to which a new data frame or remote frame has been transmitted are recorded
to the transmit history list (the transmit history list has a vacant element).
1
At least 7 entries have been stored since the host processor serviced the THL last time (i.e. read
C0TGPT). The first 6 entries are sequentially stored whereas the last entry might have been
overwritten by newly transmitted messages a number of times because all buffer numbers are
stored at position LOPT-1 when TOVF bit is set to 1. As a consequence receptions cannot be
completely recovered in the order that they were received.
Notes 1. The read value of the TGPT0 to TGPT7 bits is invalid when the THPM bit = 1.
2. If all the transmit history is read by the C0TGPT register while the TOVF bit is set (1), the THPM bit
is not cleared (0) but kept set (1), even if transmission of new data has been completed.
Remark Transmission from message buffers 0 to 7 is not recorded to the transmit history list in the normal
operation mode with ABT.