SATO CL4NX Programming Reference Manual page 561

(2) Status 4/ENQ response mode (2 ports connection or 1 port connection)
After receiving a status request command (ENQ: 05H) from the host, the printer returns the latest printer status.
CONNECT
(Port1024, Port1025
or Port9100)
CONNECT SUCCESS
Connection
Status request
(Port1024, Port9100)
(ENQ "05H")
(Port1024, Port9100)
CLOSE
（Port1024, Port1025、
or Port9100)
CONNECT END
Host
Printer
LISTEN
ACCEPT
The latest printer status
Printer status
CLOSE
LISTEN
553