1Transparent Conversion Mode - Ebyte E810-DTU User Manual

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4.2.1Transparent conversion mode

Transparent conversion: The converter converts the bus data of one format to the data format of another bus as it is,
without adding data or modifying it. The data format is exchanged without changing the data content. For the bus at both
ends, the converter is like "transparent".
The E810-DTU(CAN-RS485) can convert the valid data received by the CAN bus to RS485, and the UART outputs
the same data. Similarly, the module can also convert the data received by the RS485 to the CAN bus, and realize
transparent conversion between RS485 and CAN.
1. Frames in UART converts to CAN message
All data in the UART frames is sequentially filled into the data field of the CAN message frame. The converter
receives and converts as soon as it detects that there is data on the serial bus.The frame type and frame ID of the
converted CAN message come from the user's prior configuration, and the frame type and frame ID remain unchanged
during the conversion process. The corresponding format of data conversion is shown in Figure 4.1
If the received serial frame length is less than or equal to 8 bytes, the characters 1 to n (n is the serial frame length)
are sequentially filled into the 1 to n byte position of the data field of the CAN message (as shown in Figure 4.1, n is 7).
If the frame length is greater than 8, starting from the first character of the serial frame, for the first time the
processor takes 8 characters to fill the data field of the CAN message in turn; after the data is sent to the CAN bus, the
conversion is performed. The remaining serial frame data is filled into the data field of the CAN message until its data is
completely converted.
Figure 4.1 Frames in UART converts to CAN message(Transparent conversion)
For example：
Assume that the configured conversion into CAN message frame information is "standard frame" and the frame ID (ID1, ID2) is
set to 0060, then the conversion format is shown in Figure 4.2.
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E810-DTU(CAN-RS485) User Manual
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