Function - Renesas RZ/A Series User Manual

RZ/A1L Group, RZ/A1LU Group, RZ/A1LC Group
21.2

Function

This LSI incorporates one unit of the CAN interface (RS-CAN) which consists of two channels (CAN0
and CAN1) of the CAN controller conforming to the ISO11898-1 specifications. Table 21.9 shows the
RSCAN module specifications.
Figure 21.1 shows the RS-CAN module block diagram.
Table 21.9
Item
Number of channels
Protocol
Communication speed
Buffer
Reception function
Reception filter function
Receive message transfer
function
Transmission function
Interval transmission
function
Transmit queue function
R01UH0437EJ0600 Rev.6.00
Jan 29, 2021
RS-CAN Module Specifications (1/2)
2
ISO11898-1 compliant
• Maximum 1 Mbps
Communication speed (CANm bit time clock)
CANm bit time = CANmTq × Tq count per bit
CANmTq
m = 0 or 1
Tq: Time quantum
fCAN: Frequency of CAN clock (selected by the DCS bit in the RSCAN0GCFG register)
160 buffers in total
• Individual buffers: 32 buffers (16 buffers × 2 channels)
Transmit buffer: 16 buffers per channel
Transmit queue: Single queue per channel
• Shared buffers: 128 buffers for all channels
Receive buffer: 0 to 31 buffers
Receive FIFO buffer: 8 FIFO buffers (up to 96 buffers allocatable to each)
Transmit/receive FIFO buffer: 3 FIFO buffers per channel (up to 96 buffers allocatable to each)
• Receives data frames and remote frames.
• Selects ID format (standard ID, extended ID, or both IDs) to be received.
• Sets interrupt enable/disable for each FIFO.
• Mirror function (CAN mode receives its own transmitted messages.)
• Timestamp function (to record message reception time as a 16-bit timer value)
• Selects receive messages according to 128 receive rules.
• Sets the number of receive rules (0 to 128) for each channel.
• Acceptance filter processing: Sets ID and mask for each receive rule.
• DLC filter processing: Sets DLC check value for each acceptance rule.
• Routing function to transfer receive messages to arbitrary destinations (can be transferred to up to 8
buffers)
Transfer destination: Receive buffer, receive FIFO buffer, and/or transmit/receive FIFO buffer
• Label addition function
Stores label information together with a message in a receive buffer and FIFO buffer.
• Transmits data frames and remote frames.
• Selects ID format (standard ID, extended ID, or both IDs) to be transmitted.
• Sets interrupt enable/disable for each transmit buffer and transmit/receive FIFO buffer.
• Selects ID priority transmission or transmit buffer number priority transmission.
• Transmit request can be aborted (possible to confirm with a flag)
• One-shot transmission function
Transmit messages at intervals
(transmit mode or gateway mode of transmit/receive FIFO buffers)
Transmits all stored messages according to the ID priority.
Specification
1
= ------------------------------------- -
CANm bit time
(BRP[9:0] bits in the RSCAN0CmCFG register + 1)
= -------------------------------------------------------------------------------------------------------------------------------------- -
fCAN
21. CAN Interface
21-4