ZLG CANFDNET-400U, Руководство пользователя

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CANFDNET-400U
High-performance Four-channel CANFD Bus-to-Ethernet Converter User Manual
©2021 Guangzhou ZLG Microelectronics Technology Corp.,Ltd.
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User Manual
configured serial frame is 2, the length is 3 (in the case of extended frames). Therefore,
during conversion, the frame ID2, frame ID1, and frame ID0 in the CANFD message are
sequentially converted to the serial frame as the content in address 2, address 3, and
address 4. The data field of the CAN message will be sequentially converted to the
unfilled part of the serial frame without any modification.
4.3 Format Conversion
According to the preset CAN type, the format conversion is divided into CAN format
conversion and CANFD format conversion. The difference is that the fixed number of
bytes in the corresponding format is different. CAN format conversion with fixed 13 bytes
indicates a CAN frame, while CANFD format conversion with fixed 69 bytes indicates a
CANFD frame. As shown in Table 4.18, each CAN frame contains 13 bytes. The content
of 13 bytes includes CAN frame infor frame ID + frame data. As shown in Table
4.19, each CANFD frame contains 69 bytes. The 69-byte content includes CANFD frame
infor frame ID + frame data.
Note: In this conversion mode, the preset CAN ID is invalid, because the identifier
(frame ID) sent at this time is filled with the frame ID data in the above-mentioned format
serial frame. The configured frame type is also invalid, and the frame type is determined
by the frame information in the format serial frame.
Table 4.18 CAN fixed format serial frame
CAN fixed format serial frame (13 bytes)
Frame
information
Frame ID Frame data
1Byte 4Byte 8Byte
Table 4.19 CANFD fixed format serial frame
CANFD fixed format serial frame (69 bytes)
Frame
information
Frame ID Frame data
1Byte 4Byte 64Byte
The frame information is shown in Table 4.20, with a length of 1 byte. It is used to
identify some information of the CAN (CANFD) message, such as type and length.
Standard frames, extended frames and even CAN remote frames can be flexibly sent by
correctly configuring the frame information (the first byte of data). Details of standard
frames, extended frames and even remote frames can be obtained by correctly parsing
fixed-byte format serial frames.
Table 4.20 Frame information
Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0
FF RTR
EDL
BRS DLC3 DLC2 DLC1 DLC0

FF: identifier of standard frame and extended frame. 0 indicates a standard frame,
while 1 indicates an extended frame;

RTR: identifier of remote frame and data frame. 0 indicates a data frame, while 1