Optidrive Compact-2 Engineering Guide Issue 07.docx
9. Serial Communications
9.1. Overview
OPC-2-CON-E-IN provides support for the following fieldbus networks and functions:-
Access to all Writable Parameters
Access to all Writable Parameters
9.2. Modbus RTU
OPC-2-CON-E-IN supports Modbus RTU communication, using the 03 Read Holding Registers and 06 Write Single Holding Register commands. In
addition, Control Registers 1 – 4 may be written to using the 16 Write Multiple Holding Registers. Many Master devices treat the first Register
address as Register 0; therefore it may be necessary to convert the register numbers listed below by subtracting 1 to obtain the correct Register
address. The telegram structure is as follows:-
Command 03 – Read Holding Registers
Command 06 – Write Single Holding Register
The table shows the Modbus RTU register number corresponding to each parameter value. All values are holding registers.
All User Adjustable parameters are accessible by Modbus, except those that would directly affect the Modbus communications, e.g.
P-36 Index 1 Drive Fieldbus Address
P-36 Index 2 Baud Rate
P-36 Index 3 Comms Loss Timeout
All parameter values can be read from the drive and written to, depending on the operating mode of the drive – some parameters cannot be
changed whilst the drive is enabled for example.
9.3. CAN
The CAN communication profile in the OPC-2-CON-E-IN is implemented according to the specification DS301 version 4.02 of CAN in automation
(www.can-cia.de). Specific device profiles such as DS402 are not supported.
The CAN communication function is enabled by default after power up. However in order to use any control functions through CAN, this requires
P-12 = 7 or 8.
The CAN communication baud rate can be set by using parameter P-36. Available baud rates are: 125kbps, 250kbps, 500kbps, 1Mbps. (with
default settings as 500kbps).
The Node ID is set up through drive address parameter P-36 as well with the default value of 1.
The tables below show the Index and Sub Index required to address each parameter. All User Adjustable parameters are accessible by CAN,
except those that would directly affect the communications.
All parameter values can be read from the drive and written to, depending on the operating mode of the drive – some parameters may be
changed whilst the drive is enabled for example.
Optidrive Compact 2 provides the following default COB-ID and functions:
Synchronous message
COB-ID can be configured to other value.
Process data object.
PDO1 is pre-mapped and enabled by default.
COB-ID can be configured to other value.
PDO2 is pre-mapped and disabled by default.
Transmission mode, COB-ID and mapping can be configured.
SDO channel can be used for drive parameter access.
Guarding and Heartbeat function are supported.
COB-ID can be configured to other value.
Note
The OPC-2-CON-E-IN SDO channel only supports expedited transmission.
The OPC-2-CON-E-IN can only support up to 2 Process Data Objects (PDO). All PDOs are pre-mapped; however PDO2 is disabled by
default. The table below gives the default PDO mapping information.
Customer configuration (mapping) will NOT be saved during power down. This means that the CAN configuration will restore to its
default condition each time the drive is powered up.