p w
Thisprogrambeginsby assigninga numberof printercommandsto BASIC stringvariables(lines 1000to 1090).Youcan findmostof thesecommands near the beginningof chapter4.
The WIDTH“LPT1:“255 statementin line 1110meansintlniteline width. It preventsthe
Actualprintingbeginsin line 1120.Usingthe preassignedcommands,the programprints samplesof its differentfonts, includinga line showingall stylesin italics,followedby samplesof the printpitches,then somedouble and
Next comes the central attractionof the program: a line of text printed fourteentimesin expandingandcontractingloopsto giveabarreleffect.The workis doneby fourprintercommands:a commandsettingtherightmargin (line 14@);a centeringcommand(line 1420);a commandto vary the line spacing(lines 1440and 1490);and a commandto
Nexttheprogramreturnstonormalspacingandgivesa demonstrationofthe
The row of automobilesin the nextprintedline is createdby dGwrdoading two new characterpatterns,whichare printedin placeof the character“<” (character60). Detailscan be fwnd in Chapter5.
The final part of the programuses dot graphicsto print some “SW” IGgm withvariousdensities.Thedotpatternof thelogo wasoriginallylaid outon graphpaper,then convertedto the datain lines 2400to 2630with the help of a calculator.Each number~presents eightverticaIdots. (See “Graphics cGmmands”in Chapter4 for details.)
The patternis printedin four rows,each row is eightdotshigh and 65 dots wide.Lines 1800to 1850readthedotdataintoa stringarrayvariablenamed LOGO$.Line 1860sets the line spacingtG8/72inch so that the rows will connectvertically.The loop in lines 1870tG1960dGesthe printingin four passesof the print head.
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