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Chapter 19
CAN Controller (CAN)
Preliminary User’s Manual U17566EE1V2UM00
19.2.2
Frame types
The following four types of frames are used in the CAN protocol.
Table 19-2
Frame types
(1)
Bus value
The bus values are divided into dominant and recessive.
• Dominant level is indicated by logical 0.
• Recessive level is indicated by logical 1.
• When a dominant level and a recessive level are transmitted simultaneously,
the bus value becomes dominant level.
19.2.3
Data frame and remote frame
(1)
Data frame
A data frame is composed of seven fields.
Figure 19-3
Data frame
Note
D: Dominant = 0
R: Recessive = 1
Frame Type
Description
Data frame
Frame used to transmit data
Remote frame
Frame used to request a data frame
Error frame
Frame used to report error detection
Overload frame
Frame used to delay the next data frame or remote frame
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CRC field
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