Laser Printer Applications Manual
featurethisway,theprinterwillunderlineallsubsequentprintablecharac-
ters, includingspaces.
Sendthiscommandto turn on the underliningmode:
<ESC>&d n D
in whichfor n youput O(zero)to getfixedunderline,
or 3 to get floatingunderline.
Andsendthiscommandto turn offtheunderlinemode:
<ESC>&d@
How toprint Escape sequences and control codes
Youuse bothEscapesequencesandcontrolcodestoprint.So howdo you
printEscapesequencesandcontrolcodes?
Butyouactuallycanprintcommands,andintwodifferentways.Youwould
dothiswhenyouwantto seeeverythingexactlyasitis sentto theprinter—
for example,to debuga stringof textandcommandsthatdocsn’tprintthe
wayyouthinkit should.
The Transparentprint commandprints the string of data that follows it
withoutpaying attentionto any embeddedEsca~ sequencesor control
codes.TransparentprintevenprintsCarriageReturncodeswithoutzapping
theprintpositionbackto the leftmargin.
TouscTransparentprint,justputthiscommandimmediatelyinfrontofyour
printdata:
<ESC>&p n X
For n youspecifythenumberof bytesof datayouwantto print .
Display Functions,like the Transparentprint command, prints Escape
sequcnccsandcontrolcodeswithoutactuallyexecutingthcm.ButDisplay
Functionspaysattentionto CarnageReturncodes,so textlooksmorelike
the way it normallyprints. DisplayFunctionsalso prints commandsas
blanks,not as symbols.
DisplayFunctionsactuallyinvolvestwoEscapesequences,onetoturniton
andanotherto turnitoff.To turnon DisplayFunctions,sendthiscommand
just beforethedata youwantdisplayed:
<ESC>Y
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