Ebyte ME31-XAXX0600, Руководство пользователя

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Chengdu Ebyte Electronic Technology Co.,Ltd ME31-XAXX0600_UserManual_CN
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4.2.2 Modbus address filtering
This function can be used in certain host software or configuration screens as the host to access the device
serial port, and the gateway function of the device is used. When the slave is on the network side and the Modbus
TCP to RTU function is enabled, the presence of multiple slaves on the bus may cause data confusion. At this time,
enabling address filtering can ensure that only the specified address can pass through the device; When the
parameter is 0, data is transmitted through, and when the parameter is 1-255, data is only transmitted through the
set slave address.
4.2.3 Modbus TCP protocol data frame description
TCP frame format
：
Transaction ID Protocol ID Length Device Address Function Code Data Segment
2 Bit 2 Bit N+2 Bit 1 Bit 1 Bit N Bit

Transaction identification: It can be understood as the serial number of the message. Generally, 1 is added
after each communication to distinguish different communication data messages.

Protocol identifier: 00 00 means Modbus TCP protocol.

Length: Indicates the next data length, in bytes.
For example
：
get DI state
01 00 00 00 00 06 01 02 00 00 00 04
Transaction ID Protocol ID Length Device Address Function Code Data Segment
4.2.4 Modbus RTU protocol data frame description
RTU frame format
：
Device Address Function Code Data Segment Check code CRC
1 Bit 1 Bit N Bit 2 Bit
For example
：
get DI state command
01 02 00 00 00 04 79 C9
Device Modbus address Function Code Data Segment CRC check code
4.3 Active upload
The device supports the function of uploading analog input values at fixed time intervals. Setting the value of