Using Socket Services with CMND(490)

Section 6-8

6-8-9 UDP/IP Communications Programming Example

The following programming example illustrates transferring 100 bytes of data between an Ethernet Unit and a host computer using UDP/IP communications.

For the UDP connection, the Ethernet Unit uses a PASSIVE OPEN and the host computer uses an ACTIVE OPEN.

System Configuration

The system configuration for the program example and the Ethernet Unit system setup are shown below.

Host computer

Ethernet Unit

PLC

IP address:

196.36.32.55

IP address:

196.36.32.101

Port number:

4096

Port number:

4096

 

 

FINS network address:

01 Hex

 

 

Node address:

01 Hex

 

 

Unit number:

10 Hex

Basic Operations

CIO 000000 is turned ON to request opening a UDP socket from the Ethernet Unit.

CIO 000001 is turned ON to request closing the UDP socket from the Ethernet Unit.

CIO 000002 is turned ON to request sending data from the Ethernet Unit. Data (100 bytes) is sent beginning at D02008.

CIO 000003 is turned ON to request receiving data from the Ethernet Unit. The data that is received (100 bytes) is stored beginning at D04025.

One of the bits between CIO 000100 and CIO 000103 will turn ON if an error occurs. Refer to 6-7-5 Socket Service Request Switches for informa- tion on errors. The following areas can be used to access details about errors:

CMND(490) response codes

Response codes in results storage area

Network Communications Error Flags (A21900 to A21907)

Completion codes (A203 to A210)

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Omron CJ1W-ETN21 operation manual 149