CTI 2572-A, Installation And Operation Manual

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CTI 2572-A Installation and Operation Guide
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Offset 5 Destination - The starting address of V memory in the remote PLC that you want to update.
This address is 1 relative.
Offset 6 Command Timeout in seconds - When set to 0, the default value of approximately 9 seconds
is selected. A value of 999 specifies an infinite timeout.
Offset 7-9 Unused - Set to 0.
Offset 10-11 IP Address – UDP Only . If you set the IP Address Location bit to 1 (see offset 4 of
the C
REATE
S
OCKET
command block), you must specify the IP address of the remote
device or a multicast address in these words. If the IP Address Location bit is set to 0,
these words are ignored and the IP address contained in the C
REATE
S
OCKET
command block is used. An IP address of 0.0.0.0 (0000 0000 hex) or greater than
223255.255.255 (DFFF FFFF hex) will return an error.
Offset 12 UDP port number – UDP Only . If you set the IP Address Location bit to 1 (see
offset 4 of the C
REATE
S
OCKET
command block), you must specify the UDP port
number of the remote device. If you are accessing another 2572, you will typically
set this value to 1505 (the recommended value for the 2572-A PLC server). If the IP
Address Location bit is set to 0, this word is ignored and the port number contained
in the C
REATE
S
OCKET
command block is used.
Offset 13-15 Unused - Set to 0.
Word Transfer - Read
This function reads the contents of a designated area of V memory in the remote PLC and writes the
values in a specified area of V memory in the local PLC. You can specify the starting V memory
addresses on both the local and remote PLCs and the number of words to be transferred (up to 256
words). When the command is triggered, the 2572-A sends a request message to the remote PLC.
When the response is returned, the 2572-A verifies the response. If there is no error, the 2572-A
writes the data in local V memory. If an error is encountered, the 2572-A will post an error which
may be processed by PLC logic.
The following command block will cause the 2572-A to read the designated V memory in the remote
PLC and store the result in local V memory.
Offset Description Hex Decimal
0 Error Word 0000 0
1 Command Code (Read)
0202 514
2 Connection Number (19221-19228)
3 Source: Starting V Memory Address in Remote PLC
4 Number of Words to Transfer (1-256)
5 Destination: Starting V Memory Address in this PLC
6 Command Timeout in seconds
(0 = Use Default)
0000 0
7-9 Unused (Set to 0) 0000 0
10 IP Address of Remote Device - High 16 bits
(UDP Only: IP Address Location bit in the Create Socket