Table of Contents
Advertisement
ГК Атлант Инжиниринг – официальный представитель в РФ и СНГ
+7(495)109-02-08 sales@bbrc.ru www.bbrc.ru
Appendix C: Modbus Protocol
Operation Mode (Default = Console mode):
ET-6000 COM ports can be configured as follows:
1. VxComm (Virtual COM) (unavailable):
Enable VxComm. Remote application program can use Virtual COM (need to install
the VxComm Driver) or connect to TCP/IP port 10000 + n to access the COM port
via Ethernet. At VxComm mode, the COM port has access to any serial device.
2. Modbus/RTU:
Enable the protocol converter function to convert from Modbus/TCP to
Modbus/RTU. In Modbus/RTU mode, the COM Port can only has access
Modbus/RTU slave devices.
3. System Reserved
4. UpLink
Enable the COM Port to as a Modbus/RTU slave port.
5. Debug port:
The Modbus kernel prints out some messages, while communicating with Modbus
clients or masters.
The messages include:
(0) Receives a Modbus request response from Modbus client or master.
(1) By passes Modbus request to COM Port
(2) Send Modbus request to COM Port
(3) Check Modbus response from COM Port
(4) Send Modbus response to Modbus client or masters
6. Console:
The function disables the communication capabilities of the COM port. It's a serial
console port that allows configuration to be performed via the RS232 Port. The
commands related to the serial console are the same as the Telnet console.
Modbus/RTU Data format
There are several kinds of data formats used in the Modbus/RTU protocol that must be
changed to suit the specific Modbus/RTU devices that are connected to the COM Port.
8 data bits, none parity, 1 stop bits
8 data bits, none parity, 2 stop bits
8 data bits, odd parity, 1stop bits
8 data bits, even parity, 1stop bits (Default)
Note:
When an ET-6000 module receives a Modbus/TCP request
that not addressed to its internal registers, it first decides which COM
Port to send the request. Modbus/RTU must be enabled for this
COM Port, otherwise the request will be discarded.
Timeout (Default = 200 milliseconds)
After completing transmission of any data, the system begins to count time. If the timeout
expires, the system will stop receiving responses.
ET-6000 User's Manual, 2007, Sep., V1.1,
6PH-002-11----------158
Advertisement
Table of Contents
