ProSoft Technology MVI56-GEC - Manual (Page 84)

Reference MVI56-GEC ♦ ControlLogix Platform
User Manual Generic ASCII Ethernet Communication Module
Page 84 of 108 ProSoft Technology, Inc.
October 8, 2010
Each server has a state value in the status data area. This value is utilized by the
ladder logic to determine if a connection is present on server. The following table
defines the state status values used by each server:
Server state list
State Value Definition
-1 Server is initializing and is being set up to listen.
0 The server is waiting for a client to establish a connection.
1 The server has established a connection with a client and can send or receive
data.
1000 The server has initiated a close operation on the connection.
1001 The server is waiting for the close on the connection to complete.
1002 The server is issuing an abort (reset) on the connection. The socket is forced
closed.
1003 The server is issuing an abort (reset) on the connection due to control from user.
Client state list
State Value Definition
-1 Client is waiting for a connection request.
0 The client is waiting to establish the connection with the server.
1 The client has established a connection with the server and can send and receive
data.
1000 The client has initiated a close operation on the connection.
1001 The client is waiting for the close on the connection to complete.
1002 The client is issuing an abort (reset) on the connection. The socket is forced
closed.
Client Connection States
State Value Definition
-4 The Client is idle and not connected. It was disconnected by time value entered in
the tag for clients' connection setup Time-Out register.
-3 Server closed connection for client or server is not available.
-2 Unable to open connection with specified server.
-1 Unable to open connection with specified server because of invalid IP address.
0 The client is idle and not connected. Disconnected by the ladder logic timer.
1 The client set to connect to the server and waiting for the connection to establish.
2 The client is connected to the server and can transfer data.
3 The connection is being closed for the client.
Ladder logic should only direct messages to servers that have a state status
value of 1. The module will ignore all messages sent to servers with any other
state value.
When the ladder logic sends a message to a server, it can request that the
socket be closed after the message is sent. The server control word in the output
image is used for this purpose. Place a value of 1 in this register to gently close
the connection after the message is sent. If a value of 2 is placed in the register,
the server will abort the connection to force the socket closed (send a message
with the Reset Flag set to the client). Most applications will have the client close
the socket.