CHAPTER 3 INTERFACE
B-EP
Series
3-29
<Error transmission>
• When an error occurs during communication.
Printer
Time out
When a command packet or an
EOT cannot be received within 1
sec. after a NAK, an ACK, or a
status packet is sent, the link is
terminated. However, when a
CRC error, a framing error, or an
overrun error occurs within 1
sec., the timer is reset.
Host
PAD/Command packet
NAK/ACK/Status packet
Command packet
NAK
CRC error
When a CRC error occurs in the
received command, the printer
sends a NAK after the command
packet is received.
EOT/Command packet
NAK
Framing error, overrun error
When the reception of an EOT
or a command packet results in
a framing error or an overrun
error, a NAK is sent at that time.