Rockwell Automation 5370 Color CVIM Communications Manual - Manual (Page 106)

Chapter 5
Using the RS–232 Ports
5–38
Use the echo command to check the communications link. This command
will return the same same string of characters that are sent out with the
command. This command has the following structure:
01 00 n times Data
Where n times specifies the number of times the Color CVIM module will
echo the data field back to the host device. There is no object associated with
this command. The command is valid at any time.
For example:
01
This example will cause the Color CVIM module to return the string:
DLE ACK DLE STX 0102030405 DLE ETX BCC
If the BCC is not valid, the Color CVIM module will respond with a DLE
NAK and the command will not be executed.
If the BCC is valid, the Color CVIM module will respond with a DLE ACK.
Then the Color CVIM module will validate the command structure. If the
command is valid, the Color CVIM module will execute the command and
echo the data. If the command structure is invalid, the Color CVIM module
will not execute the command or respond.
Echoing Data