Echo (X) command


(see command description format info here)

Function:Returns NetLoader status
Command format:X
Possible replies:Annn.nnn.nnn.nnn.nnn.nnn/ppppp/m, where

        nnn.nnn.nnn.nnn.nnn.nnn - MAC-address of the DS;

        ppppp - fixed at "65535";

        m - fixed to 'L' (means that the NetLoader, not the application firmware is running).

See also:How the NetLoader is startedEcho (X) commandin the application firmware


The primary use of the Echo command is to auto-discover Device Servers on the network and to verify that the NetLoader is running. When the network host sends this command in the broadcast mode, it collects the replies from all locally attached Device Servers (hence, the name of the command). Reply from each DS contains all necessary information (MAC-address, etc.) that is needed to continue communicating with each specific DS in a non-broadcast mode. This command has its counterpart in the application firmware (see Echo (X) command ).

Information returned by the Echo command contains the following data:

MAC-address is the most important field that can be used to uniquely identify each DS! Besides, the MAC-address is used (and, therefore, must be known in advance) as a reference to the particular DS in the Select In Broadcast Mode (W) command.
Data port number field is fixed at 65535. The NetLoader doesn't use any data ports so this field is provided for format compatibility with the Echo (X) command in the application firmware.
m flag always returns 'L'. This is meant to indicate that the NetLoader is running. In contrast, when the application firmware is running this flag shows 'N'.

* This is because each DS, like any other Ethernet device, has a unique MAC-address preset during the production.