Allen-Bradley Micro800 - MODBUS2 TARPARA Data Type

Chapter 9 Communication instructions
210 Rockwell Automation Publication 2080-RM001D-EN-E - February 2015
MODBUS2LOCPARA custom command support
Custom Commands in the range of 0-255 that are not already assigned to a
Modbus command are also supported. If a custom command is used then the
LocalCfg:ElementCnt contains the number of bytes received.
The response is received into the Local Address Data and overwrites the request
data.
Example for CMD=0x2B
• Local Address Data 1:0x0E, READ_DEVICE_ID_MEI
• Local Address Data 2:0x01, READ_DEV_ID_BASIC
• Local Address Data 3:0x00, Read Vendor Object
MODBUS2TARPARA data type
The following table describes the MODBUSTARPARA data type parameters.
Parameter Data type Description
Addr UDINT Target device’s Modbus data address:
• 1 - 65536.
• Decreases by one when sending.
• Firmware uses low-word of address if the address value is greater than 65536.
NodeAddress[4] USINT Target device’s IP address. The IP address should be a valid unicast address and cannot be 0, multicast, broadcast, local address
or loop back address (127.x.x.x).
For example, to specify 192.168.2.100:
• NodeAddress[0]=192
• NodeAddress[1]=168
• NodeAddress[2]=2
• NodeAddress[3]=100
Port UINT Target TCP port number. Standard Modbus/TCP port is 502.
1 - 65535
Set to 0 to use the default value 502
UnitId USINT Unit Identifier. Used to communicate with slave devices through a Modbus bridge. Refer Modbus specification for more details.
Note that Micro800 shall not attempt to validate this value.
0 - 255
Set to 255 if Target device is not a bridge.