Omron CS1W-ETN21 User Manual
Page 113
88
DM Area Allocations
Section 4-2
TCP Socket No. (1 to 8): Number of Bytes Received (Ethernet Unit to CPU Unit)
For each TCP socket, the number of bytes of data in the reception buffer is
stored in one word. A maximum of 4,096 bytes of data can be held in the
reception buffer, but a value of only up to the maximum value (1,984 bytes)
that can be set for receive requests by manipulating control bits or using
CMND(490) is stored.
0000 hex: 0 bytes
07C0 hex: 1,984 bytes
The Data Received Flag in the CIO Area turns ON and OFF linked to this
word. This area is given a value of 0000 hex when a receive request is exe-
cuted by manipulating control bits or using the CMND(490) instruction. If any
data remains in the reception buffer after the receive request processing is
completed, the remaining number of bytes is stored and the Data Received
Flag turns ON again.
Before a receive request is executed, a check is performed to confirm that the
required data is available.
TCP Socket No. (1 to 8): Connection Status (Ethernet Unit to CPU Unit)
The connection status for each TCP socket is stored by code in this word. For
details, refer to Appendix C TCP Status Transitions.
Socket Services Parameter Area 1 to 8 (Ethernet Unit to CPU Unit)
When socket services are requested by control bit manipulation, the settings
must be made in advance in a Socket Service Parameter Area. The parame-
ters used will vary depending on the service requested. For details, refer to
Operation Manual, Construction of Applications, SECTION 6.
m+1 to m+8
Number of Bytes Received (0000 to 07C0 hex)
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
TCP connection status
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
m+9 to m+16
Offset
Socket
No. 1
Socket
No. 8
Socket option
UDP/TCP socket number (1 to 8)
Local UDP/TCP port number (0000 to FFFF Hex)
Remote IP address
(00000000 to FFFFFFFF Hex)
Number of send/receive bytes (0000 to 07C0 Hex (1984))
Send/receive data address
(Same as FINS variable area designation method.)
Timeout value (0000 to FFFF Hex)
Response code
Remote UDP/TCP port number (0000 to FFFF Hex)
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
...
+0
+1
+2
+4
+5
+6
+8
+9
m+18
m+88
...
m+19
m+89
m+20
m+21
m+90
m+91
m+22
m+92
...
m+23
m+93
m+24
m+94
m+25
m+95
m+26
m+96
m+27
m+97
...