Feature:
1. Better Monitor: The power monitor module can test current, voltage, active power, power factor, and so on, very practical.
2. Physical Layer Protocol: The physical layer uses the communication interface from UART to TTL. The baud rate is 9600, with 8 data bits, 1 stop bit, and no checksum.
3. Application Layer Protocol: The application layer uses RTU protocol for communication. Currently, only function codes such as 0x03 read hold register, 0x04 read input register, 0x006 write single register, 0x41 calibration, and 0x42 power reset are supported. The 0x41 function code is for internal use only, the address can only be 0xF8.
4. Default Setting: By default, adding a 16 digit password after the function code is 0x3721. The address range of the slave is 0x01~0xF7, and the address 0x00 is used as the broadcast address. The slave does not need to reply to the host and uses the address OxF8 as the universal address. This address can only be used in the environment of a single slave device and can be used as a calibration address.
5. CRC Verification: CRC verification uses a 16 bit format, takes two bytes, and generates a polynomial of X16+X15+X2+1. The polynomial value used for calculation is 0xA001. The CRC check value is the result of all byte checks of the data frame, except for the CRC check value.
How to Use:
The TTL interface of this module is a passive interface and requires external 5V power supply, which means that all four ports, 5V, RX, TX and GND, must be connected during communication, otherwi