> box 33,44,2,200
> box 33,44,200,2

mode 1,12
pause 1000  ' wait for mode change
cls
page write 0
' draw some random stuff
for i = 1 to 10
 circle 100+600*rnd,100+400*rnd,25+150*rnd,2,,rgb(green)
next i
t$ = chr$(149)+chr$(146)+chr$(147)+chr$(148)
text 400,285,t$+" to move, [SHIFT] for bigger step",CM,,,rgb(white)
text 400,300,"Press [ENTER] to draw line",CM,,,rgb(white)
text 400,315,"Press [ESC] to quit",CM,,,rgb(white)

x1 = 750 : y1 = 75
x2 = 100 : y2 = 200

page write 1
redraw
do
 k = asc(inkey$)
 s = 1
 if (keydown(7) and 136) <> 0 then
   s = 10 ' move faster if SHIFT pressed

   ' on my keyboard, SHIFT-DOWN ARROW gives ASCII 161 and
   ' SHIFT-RIGHT ARROW gives ASCII 163 so make correction
   if k = 163 then k = 131
   if k = 161 then k = 129
 end if
 select case k
   case 13 : paintline
   case 27 : exit do  ' escape to quit
   case 128 : y2 = y2 - s * (y2 >  10) : redraw  ' cursor up
   case 129 : y2 = y2 + s * (y2 < 590) : redraw  ' cursor down
   case 130 : x2 = x2 - s * (x2 >  10) : redraw  ' cursor left
   case 131 : x2 = x2 + s * (x2 < 790) : redraw  ' cursor right
 end select
loop

end

sub redraw
 cls
 line x1,y1,x2,y2,,rgb(yellow)
end sub

sub paintline
 page write 0
 line x1,y1,x2,y2,,rgb(blue)
 page write 1
end sub