Star Micronics 8 Series Applications Manual page 35

P
Moving the print position: a preview
Wlthdot-matnxanddaisywheel p rinters,youpickwheretoprinton thepage
eitherby movingthepnntheadbackandforthor by movingthepaperitself.
Laserpnntemdon'thaveprintheads, b uttheprincipleremainsthesame:you
haveto sayexactlywhereonthepageeachpictureandstringof textis to go,
so each page can be constructedin the printer'smemory.
Insteadof talkingaboutprintheadswe talk aboutmovingthe print
position
(some people call it moving the "cursor," using the computer-screen
analogy).Horizontally, y oucanmovetheprintpositionwithbackspaceand
carriageretumcommands. V ertically, y oucanmovetheprintpositiondown
thepagebyprintingsomanylinesper inch,or by sendingline-feedandhalf
line-feedcommands.You can also move to tab settingsboth horizontally
and vertically(handyfor tablesand blankforms,or makingroomfor your
diagrams).
But those aren'tall. Dependingon whichprinteremulationyou are using,
you" can tell the Star LaserPrinter8 to movethe print positionverticallyor
horizontallyin incrementsof:
1/10,1/12or similarfractionsof an inch (pitch settings),
1/48,1/60,1/72,1/120or 1/216inch (lineor columndefinitions),
l/3CN) inch (dots),or
1/720inch (tenthsof a point).
These incrementsreflect the history of twentiethcentury printing.
Pifch,
referringto thenumberof charactersprintedin eachhorizontalinch,derives
from how typewritersspacetheircharacters.
Lines
and columnswere first
used by earliercomputerprinters(on whichthey are calledhorizontaland
verticalmotionindexes).You alreadyknow aboutthe Star LaserPrinter8
being ableto print 300 dots to the inch.And the unit by whichtypesetters
have measuredtext for centuriesis the
point,
about l/72nd of an inch.
One hint aboutmovingthe printposition:you can confuseyourselfif you
usemorethanoneor twodifferentunitsduringthe samesession.So decide
beforehand how accurately you need to move the print position (not
forgettingany graphicsyou wantto include).Then stick to the unit(s)you
choose.
The commandsthatmovethe printpositionin all thesewaysare described
in chapters4 through7, withthe specificprinteremulationyouwantto use.
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