CHAPTER 3 INTERFACE
B-EP
Series
3-38
3.2.7
PRINTER STATE TRANSITION
(LABEL MODE)
Printer state transition
Event
Ensuring link
Issue
Command
reception
End of issue
Status Request
Command
EOT reception
Time out
CRC error
Syntax error,
Storage error,
State
Store
Command
reception
End of storage
reception
Error
during
issuing
Wait state for
the link
S1
NAK
transmission
→
S2
— — — — — — —
Wait state for a
command after
the NAK
transmission
S2
— Normal
ACK
transmission
Command
analysis
→
S3
— Normal
Status
transmission
→
S3
End of link
NAK
transmission
Error
Status
transmission
→
S4
— Error
Status
transmission
→
S4
→
S1
→
S1
→
S2
→
S1
Wait state for a
command/EOT
after the ACK
transmission
S3
— ACK
transmission
Command
analysis
EOT has been
received
ACK
transmission
(NOTE 1)
Status
transmission
Store
Command
Start of storage
process
→
S3
End of link
(NOTE 2)
NAK
transmission
→
S1
Issue
Command
ACK
transmission if
the issue is
completed.
(NOTE 1)
EOT
has
not
been received
→
S1
If the issue is
not completed
→
S3
→
S3
→
S3
→
S3
Status Request
Command
→
S1
→
S1
→
S2
→
S1
Wait state for
an EOT after
the status
transmission
S4
— Status
transmission
→
S4
— Status
transmission
→
S4
Clear of error
→
S1
End of link
→
S1
—
→
S1
NOTES:
1. Only when the ACK transmission for the process end is specified by the Data Print
Command, an ACK is sent after an issue is completed.
2. An ACK for the command process end is also sent, when the time out occurs during the
wait state for an EOT.
Host state transition
Event
State
NAK reception
ACK reception
Status
reception
Time out
(NOTE 1)
CRC error
Framing error
Overrun error
Activation of
transmission to
the printer
Wait state for a
NAK for the link
request
S1
Command
transmission
→
S2
→
S1
→
S1
→
S1
→
S1
—
Wait state for
an ACK/status
after the
command
transmission
S2
Command
retransmission
→
S2
Middle block
Command
transmission
→
S2
Final block
EOT
transmission
→
S3
or
→
S4
EOT
transmission
→
S4
→
S4
→
S4
—
Wait state for
an ACK after
the EOT
transmission
S3
—
→
S4
→
S4
→
S4
→
S4
—
Key entry mode
S4
→
S4
→
S4
→
S4
— —
→
S1
NOTE:
The retry count is arbitrarily determined by the host.