Laser Printer User Manual

SomepmgrammemcalltheXONand XOFFcontrolcodes“kissonandkiss
off’ otherscallthesameprotocolDC1andDC3(fordevicecontrol).Either
way,thesecodesletyourprinterruntheshow,tellingthecomputerwhento
startandstopsendingdata.Yourprinterasksto havedataheldbackwhen
its memoryis nearlyfullor whenit sensesan ERRORcondition.
DTR(DataTerminalReady)protocoldoesthe samethingslightlydiffer-
ently.Theprintersendsa continuoushigh-voltagesignaloverthe cableas
long as it can accept data, but drops the voltage to say “whoa” to the
computer.
Look in your computer’soperationsmanual,in the sectiondealingwith
communicationsprotocols,to see whichis bestfor yoursystem.You can
sticktotheprinter’sdefaultsifyourcomputerdoesnotusetheDTR,butdoes
use
XON/XOFF.
2.2.2 Checkingyour connections
Yourcomputerandpnntermayhavetroublecommunicatingwhenyoufirst
introducethemtoeachother.Thequickwayto findoutif yoursettingsand
printercableareworkingisto sendyourprinteraprintoutfromyourscreen
(CTRL-PwithMS-DOS).
Whenthat’sdoneyouwillalsohaveto presstheprintbuttonontheprinter,
whichmakestheprinteradvanceto a newsheet.No laserprinterprintsand
ejectsapageuntilit’stoldto feedaform,oruntilithasreceivedallthelines
thepagecanhold.
If your Star LaserPrinter4 doesn’tprint what’son the computerscreen,
recheck your connectionsand interface settings. With an applications
programlikeLotus1–2–3orMicrosoftWord,youuseaprintersetuproutine
to match your computerwith yourprinter’soperatingcharacteristics.So
double-checkyoursoftwaresettings;yourcomputer’soutput,forexample,
mightnot be goingto theproperport.
2.2.3 Printeremulations
OK, you’vegot yourprinterand computerconnectedproperly.Now let’s
focuson howyourprinterworks.
Your Star LaserPrinter4 understandsand uses the same commandsas
severalearlierkindsof printers.Yourprinterworksby emulatingone of
these:
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