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Using Socket Services with CMND(490) Section 6-8
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
Close
Bit
TCP
Open
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 TCP PASSIVE OPEN REQUEST command data bytes: 18 (0012hex) bytes
Number bytes to receive: 4 bytes
Remote Ethernet Unit designation
Network address: 01
hex
Node address: 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 TCP CLOSE REQUEST command data bytes: 8 b
y
tes
Number bytes to receive: 4 bytes
Number bytes to receive: 4 bytes
006EH 0004H 0001H 0110H 0000H 0032H
0123456789
D00020
CMND(490) control data for TCP SEND REQUEST
Command format = 10 bytes + 100 bytes send data
Number of TCP SEND REQUEST command data bytes: 110 (006E
hex
) bytes