Star Micronics 4 manual Printingdots, Whatdo graphicscommandslook like?

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5.6GRAPHICS

If you are using a commercialgraphicsprogram,such as Lotus 1-2-3, you won’tneed to use the commandsin this section.Usuallyyou’lljust draw your imageon your screenand then send it to the printer.

Shouldyouwantto sendyourowngraphicscommandsinFX-850emulation mode, though, it’s best to start off knowing a little binary arithmetic.If you’re rusty on binary you can reviewcomputerarithmeticin Chapter 1. We’llassumeyou alreadyknowelementaryprogrammingin the following discussion.

5.6.1 Printingdots

FX-850 emulationprints graphics as lines eight pin-dotshigh. You just specifywhichof the eightdots to print for each dot-widecolumn.

That soundseasy,but it can be a lot of work.It meansspecifyingan eight- bit binary number60 to 240 times per inch, right ac~ossthe page. That’s maybe 2000 calculationsfor every line! As you can imagine, graphics softwareuses plentyof programloops.

The figurebelowshowsthevalueof each dot on the left. The exampleson the rightshowhow youwouldaddup dots,to tell yourprinterwhatdotsto print for a coupleof columns:

128 ●	128 ●	0
840	o	640
32 ●	32 ●	0
16 .		0
80	:	80
40	40	0
20	0	20
10	10	0
	165	74

5.6.2 Whatdo graphicscommandslook like?

To print FX-850graphicsyou have to makefour decisions:

●Whatline spacingdo you wantto use?

●Howmanydotsdoyouwantperhonzontal inch?Thatis, whatdensity do YOUWtU’lt?

●Howwideisthepage areaonwhichyouwantto ’’paint”yourgraphics?

●Whatdot patternwill yourdata have?

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