How can I use Modbus TCP with my V16Pro?

Modbus TCP uses individual "bits" for discrete inputs and outputs. The V16Pro has a ModbusTCP client protocol that can be used to communicate with ModbusTCP Server. 

These bits can be viewed in WinScriptLive using two different methods. Both of these methods use the "Generic Modbus" product file(C:\Program Files (x86)\Alcorn McBride Inc\Product Files\Modbus_Generic.prd)

Method 1: Manual Reads and Writes

With this method, each command to the Modbus device must be sent as a separate line. Individual addresses are typed into each line. "Write Coils" can be used to turn on individual bits (outputs). "Read Coils" can be used to read the status of these outputs. "Read Discrete Input" can be used to read a certain bit (input).  

Analog values (entire words) may be set using "Write Single Register"

If individual bits of entire words need to be set, the user may define a "Device Variable". "Aliases may also be used to help keep track of individual bit names. (See below)



In the attached example, Sequences 1-10 and Device #1 (ModbusManual) demonstrates using the manual method. 


Method 2: Slave IO

In this method, polling is automatically handled by the V16Pro. Discrete IO (individual input and output bits) are placed as "inputs" or "outputs" prefixed by the name of the device. 

The number of input/output bits that you want to use is specified when setting up the device on the "Devices" screen under the "Edit" wizard.

In the attached example, sequences 13-19 and device #2 (ModbusSlaveIO) demonstrates using this method. 

Note: for some devices, the .prd file may need to be modified to change the starting address of the "read coils" or "write discrete input".  

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