RL78/F13, F14 CHAPTER 18 CAN INTERFACE (RS-CAN LITE)
R01UH0368EJ0210 Rev.2.10 1394
Dec 10, 2015
18.6.4 Transmit History Function
Information of transmitted messages can be stored in the transmit history buffer. Each channel has a single transmit
history buffer that can contain 8 sets of transmit history data.
A message transmit source buffer type can be selected by the THLDTE bit in the THLCCi register. Whether to store
transmit history data for each message can be set by the THLEN bit in the CFIDHk register.
After transmit completes successfully, information of the following transmit messages is stored in the transmit history
buffer as transmit history data. After successful completion of transmit, process may be delayed by up to 38 clocks of f
CLK
before the transmit history data is stored.
• Buffer type B'01: Transmit buffer
B'10: Transmit/receive FIFO buffer
• Buffer number Number of source transmit buffer or transmit/receive FIFO buffer.
This number depends on buffer types. See Table 18-11.
• Label data Label information of transmit message
Table 18-11. Transmit History Data Buffer Numbers
Buffer type
Buffer No.
B'01 B'10
B'00 Transmit buffer 0 Numbers of transmit buffers linked to transmit/receive FIFO
buffers by the CFTML[1:0] bits in the CFCCHk register.
B'01 Transmit buffer 1
B'10 Transmit buffer 2
B'11 Transmit buffer 3
Label data is used to identify each message. A unique label data can be added to each message transmitted from a
transmit buffer or transmit/receive FIFO buffer.
Transmit history data can be read from the THLACCi register. If it is attempted to store new transmit history data while
the buffer is full, the buffer overflows and the new data is discarded.