Galil recently enhanced the feature set of the RIO-471x0 Pocket PLC to include more Modbus functionality. These new enhancements now allow the RIO Pocket PLC to communicate seamlessly to Think & Do software via Modbus TCP/IP.

Think& Do is a software package offered by Entivity that allows a standard computer to act as a PLC for remote IO units. This type of software is often referred to as a "soft PLC". One of the key advantages of the Think & Do software suite is it's implementation of numerous communication protocols, including Modbus TCP/IP.  Modbus TCP/IP is one of the only truly open communication protocols in the automation industry and is supported by a majority of automation devices including PLC's, HMI's, sensors and much more.

In order to take advantage of every feature that the Think & Do software provides, along with numerous other Modbus TCP/IP devices, Galil has recently added to the RIO's Modbus feature set. These features include:

1) Supporting Modbus function code 15 as a slave

2) Swap how function codes 3 and 4 work(MV command)

3) Set data transfers as 16 bit integers as opposed to 32-bit floating point values(MI command)

Function Code 15

In RIO firmware version 1.0a function code 15 is only supported as a Modbus master. In version 1.0b(the standard version which now ships), Galil has added support for function code 15 as a Modbus slave. This allows other devices to set multiple digital outputs on the Galil at the same time

MV Command

The RIO will default to answering function code 3 requests with analog input data and function code 4 requests with analog output data. By setting MV1 the RIO will then respond to function code 3 requests with analog output data and function code 4 requests with analog input data.

MI Command

By default the RIO will conduct data transactions for function codes 3,4 and 16 as 32-bit floating point values . By setting MI1, the RIO will then use 16-bit integers instead.

For more details on all of these features please refer to the RIO user manual and command reference or talk to an Applications Engineer at Galil. 1-800-377-6329