Intermec EasyCoder F4 – Installation & Operation IPL Version, Ed. 1 37
Chapter 6 Setting Up the Printer
Setup Parameters, cont.
Serial Communication,
cont.
Protocol
• XON/XOFF (default)
In the XON/XOFF protocol, data fl ow control is achieved by
using XON (DC1) and XOFF (DC3) characters. Message blocks
are not required to be bracketed by the Start of Text (STX) and
End of Text (ETX) characters. However, if the ETX is sent, the
printer will ignore all characters until the STX is detected. The
message length in this protocol is unrestricted. That is, the printer
processes information as it is being downloaded and stops when
there is no more information.
XON/XOFF protocol conforms to generally accepted industry
standards. No end-of-message response is sent to the host other
than XOFF. In addition, a DC3 will be sent back if the printer is
offl ine. An XON will be sent on power up.
Since DC1 and DC3 are used for data fl ow control, the printer status
characters are different than those of the Standard Protocol. If the
host ignores the printer’s XOFF, the printer will resend an XOFF
after receiving every 15 characters from the host.
Condition Character
Buffer already full GS
Ribbon fault US
No label stock EM
Buffer now full DC4
Printhead hot SI
Label at strip pin FS
Label skipping DC2
Printing DC2