JVL MAC00-EC4, User Manual

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JVL Industri Elektronik A/S - User Manual - Ethernet for MAC and MIS motors 163
7.2 Commissioning
7.2.2 Mechanical installation
The network cables must be connected to the two M12 connectors marked “L/A IN”
and “L/A OUT” at the MAC module and “CN2” and “CN3” at the MIS/MIL motors.
The cable from the IO CONTROLLER is connected to either of the two ports. In the line
topology, if there are more slave devices in the same line, the next slave device is con-
nected to the second port. Standard CAT 5 STP cables can be used. It is not recommend-
ed to use UTP cables in industrial environments, which is typically very noisy.
7.2.3 Network configuration
To enable communication through the Ethernet network, the module needs a valid IP
address. This is either done manually in MacTalk, or DHCP is enabled in Mactalk, and
then the IP address, net mask and gateway is automatically obtained from a DHCP serv-
er. If DHCP is enabled then a DHCP server has to be available on the local network.
7.2.4 Communication description
Connect to Modbus TCP module by opening a TCP client connection to the module IP
address on port 502. It’s possibly to have only one open connection at a time.
Or connect via UDP, by just sending UDP requests to port 502. With UDP it is possible
to have several masters at the same time. It is even possible to have one TCP master and
several UDP masters connected at the same time.
The registers in the motor and in the module are all 32 bit. To comply with the clean 16-
bit Modbus standard, a 32-bit register must be read or written as two consecutive 16-bit
registers. The register address mapping follows the normal documented register num-
bers but the address field, must be multiplied by two, so to read or write register 3,
P_SOLL, use the address 6. Thereby, enabling transfer of one 32 bit register, as two 16
bit registers, where the least significant 16 bit “register” is transmitted first (see exam-
ples).
It is possibly to access both motor registers and Modbus TCP module registers. Motor
registers is accessed by addressing register 0x00 – 0x1FE (for motor register 0-255), and
module registers is accessed by addressing 0x8000 – 0x807E (for module register 0-64).
The Modbus TCP extension includes 7 additional bytes to the original Modbus protocol
which allows for transport over the TCP/IP layers – the MBAP header. So the frame for-
mat looks like this (excluding TCP/IP header):
| -
MBAP Header
- | -
Function Code
- | -
Data
- |
The MBAP Header (ModBus Application Protocol Header) consists of 7 bytes of infor-
mation:
Function codes
The MAC00-EMx/MIS/MILxxxxxxEMxx Modbus TCP module supports three function
codes:
Transaction Identifier 2 bytes
Identification of Request/Response transaction
– copied from request to response
Protocol Identifier 2 bytes 0 = Modbus protocol
Length 2 bytes number of following bytes – includes the unit identifier
Unit Identifier 1 byte identification of remote slave.
0x03 Read holding registers
0x10 Write multiple registers (up to 32 modbus registers = 16 x 32bit registers)
0x17 Read/Write multiple registers