1. OptoControlSDKR40.exe Driver
2. ReadMe.Txt File Contents

ReadMe.Txt Driver File Contents (OptoControlSDKR40.exe)

ReadMe.Txt for WinSockTerm
4/11/97

What is this sample for?
-----------------------
This sample demonstrates how to use Sockets to access an RTU (an Opto 
Controller) via ethernet using Sockets. This sample uses Microsoft Windows 
Sockets and runs on NT or Win95. This sample is intended to help users 
implement TCP/IP sockets communications from UNIX, VAX or other platforms.

How does the RTU talk using TCP/IP?
----------------------------------
Using the sockets networking interface, this sample works similar to a
telnet program. It sends a command to the Host task on the RTU/Controller
and displays the response. Unlike a telnet program, the first two bytes of
the response from the RTU's Host task contain a two-byte error code which
is normally zero. Since, under normal conditions, the first two bytes are
zero a 'normal' telnet program would interpret the response as a null string
and as a result would not display the response. This sample handles the two-
byte error code displaying the numeric error code and the rest of the 
response after the error code. Here's an example using the PTIME command
which tells the RTU to respond with the time:
    Command:  PTIME 
    Length of command: 5.

    Response: <2 null bytes>12:30:59
    Length of response: 10


What commands can be used with the Host task?
--------------------------------------------
See two documents that are included with OptoControl in the OptoControl SDK:
1) Cool4th - these are commands in the RTU kernel. 
2) HostWords - these are additional commands that are downloaded

What can be done with this sample?
---------------------------------
Three things can be done with this sample:
1) Talk to a host task and issue commands the same way that you might use
OptoTerm.Exe to issue a PTIME command. This is of interest to UNIX 
programmers who want to write a sockets program to access the Host task on 
an RTU over an ethernet connection. The Host task provides access to read
and write all data on the RTU.
2) Talk to another instance of this application to test your TCP/IP setup.
This sample can be either a 'caller' or a 'listener'.
3) Listen for connection initiated by the controller and receive data dumps
sent by the controller on a report-by-exception basis rather than a polled
basis. This mode is similar to a telnet server and would be of interest to
UNIX programmers who want to create their own command parser on the RTU.
Using OptoControl, the RTU can be programmed to accept or initiate telnet 
connections and then respond to commands or simply volunteer data to a host.

How is this sample organized?
----------------------------
The WinSockTerm.MAK project file is compatible with the Visual C++ 
development environment. The main dialog is in the ChatDlg CPP and H files. 

How can the 'pertinent' code be found?
-------------------------------------
All of the WinSock work is done in the main dialog in ChatDlg.CPP. 
Search for 'WinSock' to find pertinent sockets code and comments.

(end of ReadMe.Txt)