elsner elektronik 30146, Установка и настройка

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5 Transfer protocol
Weather Stations P03/3-Modbus(-GPS) • Version: 07.06.2022 • Errors excepted. Subject to technical changes.
Setting of the slave’s address:
The slave address is set with the help of the 8-bit DIP switch “Address”. If all switches
are in the OFF position, Address 1 is active. Address 0 is reserved for broadcast mes-
sages; addresses greater than 247 are not valid.
The coding of the address is binary. For the address 47, you must e.g. set the switches
3, 5, 6, 7 and 8 to ON.
Interface parameters:
The interface parameters are set with the help of the second 8-bit DIP switch. If the first
4 switches are in the OFF position, the transfer rate amounts to 19,200 bauds. If one of
these switches is set to ON, the corresponding baud rate is applicable.
Parity: If the two switches “ODD” and “NONE” are set to OFF, the parity is EVEN. Only
“ODD” or “NONE” can switch the corresponding parity check.
Switch “Mobu EE”: no function.
Switch “Term.”: bus termination 124 ohms
3.3. Notes on commissioning
The correct wind value may only be supplied approximately 60 seconds after the sup-
ply voltage has been connected.
4. Transfer protocol
4.1. P03-Modbus request string from the master
Example query string for reading all data:
0x01 0x04 0x00 0x00 0x00 0x11 0x30 0x06
Byte
No. Variable Meaning
0 Slave address xx
1 Command 04H Read Input Registers
2 Start address High Byte xx Register start address
3 Start address Low Byte xx
4 Number of words High Byte xx Number of registers to be read
5 Number of words Low Byte xx
6 CRC Low Byte xx
7 CRC High Byte xx