Intermec EasyCoder 501XP, User Manual

Page: 82 / 192

Chapter 6 Setting Up the Printer
Setup Parameters, cont.
Serial Communication, cont.
·ENQ/ACK
Inthisprotocol,thecommunicationiscontrolledbythe
controlcharactersENQ(ASCII05dec.)andACK(ASCII06
dec.)beingtransmittedonthesamelineasthedata.Thes
end-
ingunittransmitsENQatregularintervals.Iftherespo
nse
ACKisnotreceived,thetransmissionisheldupawaiting
anACKcharacterfromthereceivingunit.Bydefault,ENQ
/
ACKisdisabled.
·XON/XOFF
Inthisprotocol,thecommunicationiscontrolledbythe
controlcharactersXON(ASCII17dec.)andXOFF(ASCII
19dec.)beingtransmittedonthesamelineasthedata.XO
N/
XOFFcanbeenabled/disabledseparatelyfordatareceiv
ed
fromthehostbytheprinter(printersendsXON/XOFF)and
fordatatransmittedtothehostfromtheprinter(hostse
nds
XON/XOFF).
XOFFissentfromtheprinterwhenitsreceivebufferis
fi
lledto75%,andthetransmissionfromthehostisheld,
waitingforanXONcharacter.Whenenoughdatahavebeen
processedsothereceivebufferis
fi
lledonlyto50%,theprinter
sendsanXONcharacterandthehostresumestransmitting
data.ThesameprinciplesapplytoXON/XOFFsentbythe
host,evenifthepercentage
fi
guremaydiffer.
Bydefault,XON/XOFFisdisabledfordatabothways.
New Line
Selectsthecharacter(s)transmittedfromtheprintertos
pecifythe
switchingtoanewline.Therearethreeoptions:
LF
·CR