Yaskawa MotionWorks IEC Hardware - Manual (Page 58)

MotionWorks IEC Hardware Configuration – 2013-03-26 55
Modbus TCP Status Variable
This variable reflects the connection status. It can be used in the
application program to determine if the connection to the remote device is
active and the data is valid. The status WORD can be compared to
16#1000, which means that the connection is good. If bits 0 or 1 are on,
the connection is not active, and the controller is attempting to reconnect
to the remote device.
The status variable is only available when the MPiec controller is the client
or master of remote devices.
NOTE: If the status variable has a value of zero as observed in the Global
Variables list, the controller may not be running the application program.