Ethernet Units Operation Manual

147
Using Socket Services with CMND(490) Section 6-3
• One of the bits between CIO 000100 and CIO 000103 will turn ON if an
error occurs. Refer to 6-2-2 Response Codes for information 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)
Program Memory Maps
The send and receive data and bits (flags) used by the program are shown in
the following diagrams. The following example shows how the memory maps
are structured.
Legend
DM Area
0012H 0004H 0001H
012
D0000
CMND(490) control data
00
76543210
CIO 0000
15 to 8
TCP
Send
Bit
TCP
Close
Bit
TCP
Open
Bit
TCP
Receive
Bit
Describes the meaning of the data.
Indicates the contents of D00000 is 0012 Hex.
Indicates the contents of D00001 is 0004 Hex.
Indicates that CIO 000001 is used as the TCP Close Bit.
Indicates that CIO 000000 is used as the TCP Open Bit.
0012H 0004H 0001H 0110H 0000H 0032H
0123456789
D00000
Number of bytes to send: 18 (0012
hex)
Number bytes to receive: 4 bytes
Remote Ethernet Unit designation
Network address: 01
hex
Node number: 01hex
Unit address: 10hex
Port number: Port #0
Response monitor time: 5 s
CMND(490) control data for TCP PASSIVE OPEN REQUEST
0008H 0004H 0001H 0110H 0000H 0032H
0123456789
D00010
CMND(490) control data for TCP CLOSE REQUEST
Number of bytes to send: 8 bytes
Number bytes to receive: 4 bytes