CTI 2572-B - Page 50

CTI 2572-B / 2500C-2572-B Installation and Operation Manual 44
If an error is encountered writing the data to the remote PLC, no data will be read from the remote PLC; an
error message indicating the write failed will be returned. If an error is encountered reading data, an error
message indicating the read failed will be returned. In either case, the module will set the applicable error bit
and write the error code into the Command Error Word.
The following command block is used for the Exchange command.
Offset
Description
Hex
Decimal
0
Command Error Word
0000
0
1
Command Code (Exchange)
0203
515
2
Connection Number (19221 - 19228)
3
Write Source: Starting V Memory Address in Local PLC
4
Number of Words to Write (1-254)
5
Write Destination: Starting V Memory Address in Remote PLC
6
Command Timeout in seconds (0=Use Default)
0000
0
7
Read Source: Starting V Memory Address in Remote PLC
8
Number of Words to Read (1-256)
9
Read Destination: Starting V Memory Address in Local PLC.
10 IP Address of Remote Device - High 16 bits
(UDP Only: IP Address Location bit in the Create Socket
command must be set to 1)
11 IP Address of Remote Device - Low 16 bits
(UDP Only: IP Address Location bit in the Create Socket
command must be set to 1)
12 UDP Port Number of Remote Device
(UDP Only: IP Address Location bit in the Create Socket
command must be set to 1)
13 - 15
Unused (Set to 0)
0000
0
Offset 0 Command Error Word - Your PLC logic should set this to 0 so that any previous error code is
cleared. If a processing error is encountered, the module will write an error code into this
word.
Offset 1 Command Code - The Command Code for E
XCHANGE is 515 (hex 0202).
Offset 2 Connection Number - Use the connection number that was established in the C
REATE SOCKET
command block.
Offset 3 Write Source: Starting V Memory - Enter the first V memory location in the local PLC which
contains the values which you wish to write to the remote PLC.
Offset 4 Number of Words to Write - Enter the number of words you want to write.
Offset 5 Write Destination: Starting V Memory - Enter the beginning address of the V memory block
in the remote PLC to which you want to write this data.
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.