SATO CL4NX Programming Reference Manual page 701

3) Sequence
1. Status 4/ENQ response mode (2 port connection or 1 port connection)
Status 4/ Cyclic response mode (2 port connection or 1 port connection)
Output print status in constant period (500ms-1000ms interval)
The latest Printer Status is returned after printer receives status request command (ENQ:05H)
from host.
Status request
(Port1 or Port3)
(ENQ[05H])
2. Status 4/ENQ response mode (2 port connection or 1 port connection)
Printer sends the latest printer status after Status after receiving status request command
(ENQ:05H) from host.
CONNECT
(Port1, Port2
or Port3)
CONNECT success
Status request
(Port1, Port3)
,
(ENQ[05h])
CLOSE
(Port1, Port2
or Port3)
CONNECT End
3. Status 3, Status 5/ENQ response mode (1 port connection)
Printer sends ACK when printer receives print request from host and Printer Status is returned
when printer receives status request command (ENQ: 05H) from host.
HOST
CONNECT
（Port1, Port2
or Port3)
CONNECT success
connect
CLOSE
（Port1, Port2
or Port3)
CONNECT End
HOST
connect
PRINTER
LISTEN
ACCEPT
The latest printer status
Printer status
(Port2, Port3)
CLOSE
LISTEN
699
PRINTER
LISTEN
ACCEPT
Printer status(About 500-1000ms interval)
Port2 or Port3
Latest printer status
Printer status
(Port2 or Port3)
CLOSE
LISTEN