Most programminglanguages,and someversionsof BASIC,let you treat the printeras a fileto whichyoucan senddata. Whenyou writea program withoneof theselanguagesyou“open”theprinterfile,printintoit,andthen “close”the file when you’redone.Thisprogrammingjargon soundsfunny if you‘renot used to it— but it works.
A few programminglanguageslet yousendcommandsto theprintera third way. Applesoft BASIC is one. With it, you can switch between printer outputand screenoutput.
Printer emulations
You noticedthat we said “in
Unfortunatelythose printers often use different escape sequences for exactly the same function.Those printers, moreover,provideescape se- quences for functionsthe Star LaserPrinter8 doesn’t need, such as the Diablo’sChangePrintwheelcommand.(Printwheels— sometimescalled “daisywheels”- are flatmetalor plasticprintelementsthatholdcharacters out from a hub on “petals”.)Whenyourprintergets a commandit doesn’t support,it just ignoresthe command.
Macrosaresinglecontrolcodesyoucandefineyourself,whichdo the work of awholelongseriesofprintercommands.Ifyouareaprogrammeryouwill be happyto hear the Star LaserPrinter8 supportsup to 99 macrosat once.
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