User`s manual

Serial Parameters - RS-232 & RS-422
85
You can select the poll character and the poll delay time from the
printer control panel. You can also enable or disable Series 1 Idle
from the control panel. Descriptions of these parameters start on
page 83.
NOTE: When using the SERIES 1, 1 CH protocol, be careful with
the transmission of binary data (control codes, bit images,
etc.) since the printer discards poll characters.
SERIES 1, 2 CH
When you select the Series 1 with 2 Characters protocol, the printer
behaves exactly the same as the Series 1 with 1 Character
protocol, except that the printer sends two-character responses to
the host. These response characters are listed in the following
table:
NOTE: When using the SERIES 1, 2 CH protocol, be careful with
the transmission of binary data (control codes, bit images,
etc.) since the printer discards poll characters.
DTR Protocol
The printer controls the data flow by sending this hardware signal to
the host. If there is enough room in the printer buffer, the printer will
send a high signal; if the buffer is full, the printer will send a low
signal. DTR tells the host if it is safe to send more data. (If the host
sends data during an unsafe condition, data will be lost.) DTR is not
available when RS-422 is selected.
Online State Buffer State Response Characters
Online Buffer Empty 1 CR
Buffer Full 3 CR
Offline Buffer Empty 0 CR
Buffer Full 2 CR