Receive Using Transmit/Receive Fifo Buffers - Renesas RH850 Series Application Note

RH850 Series
4.

Receive Using Transmit/Receive FIFO Buffers

The transmit/receive FIFO buffer can be used in receive mode, transmit mode, or gateway mode (only receive mode
is described in this chapter).
There are 3 transmit/receive FIFO buffers per channel dedicated to each channel. The transmit/receive FIFO buffer
set to receive mode can store as many messages as the number of buffers, just like the receive FIFO buffer.
When a received message is stored in the transmit/receive FIFO buffer set to receive mode, the value of the
corresponding message count display counter (the CFMC [7: 0] bit of the CFSTSk register) is incremented.
Received messages can be read from the CFIDk register, CFPTRk register, and CFDFd_k register (d = 0 to 15). The
transmit/receive FIFO buffer can be read from the oldest message.
When the value of the message count display counter matches the buffer value of the transmit/receive FIFO buffer
(the value set by the CFDC [2: 0] bit of the CFCCk register), the transmit/receive FIFO buffer becomes full (the CFFLL
flag in the CFSTsk register is "1").
When all messages are read from the transmit/receive FIFO buffer, the transmit/receive FIFO buffer becomes empty
(the CFEMP flag in the CFSTSk register is "1").
For the configuration settings for using the transmit/receive FIFO buffer, refer to "CAN Configuration Application
Note".
R01AN6028EJ0100 Rev.1.0
May 10, 2017
CAN Receive Procedure (CAN FD Mode)
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