Allen-Bradley 1747-PBASE, Руководство по программированию

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Publication 1746-PM001A-US-P
6-12 Writing Programs Using the BASIC Development Language
7. Type the screen setup comment and the screen commands that follow it. Note
that these commands are programming macros. See Appendix A of this
manual.
{screen setup}
background_Black( )
High_Intensity ( )
foreground_Yellow ( )
cls ( )
8. Type the print statements comment and the first print command. Print
commands can be abbreviated as
P.
or the full command
PRINT
can be
entered. A print command on a line by itself results in a blank line being
printed.
{print statements}
print
You are now ready to enter the print commands that cause a boxed-in message
to appear on the screen when this program is run. Since you are using the
line-draw feature here, it is best to first enter the text and then draw the lines in
afterwards. Line drawing is performed in Overstrike mode only, so be sure that
you have spaces and not text wherever you expect to draw a line.
9. Type the print statements as shown except for the lines. Leave spaces where
you expect to draw a line.
P.tab(10),” “
P.tab(10),” WARNING “
P.tab(10),” Use of this machine is restricted “
P.tab(10),” “
10. When you are ready to draw the box, pull down the Other menu and select
Linedraw.
11. Position the cursor to a corner of the box by using the arrow keys. Line
drawing does not begin until you hold [
Shift
] while moving with the arrow
keys. Press [
F2
] to go into Double line mode. Press it again to go into Erase
mode (to erase lines), and press it again to go back to Single line mode.
12. Press and hold [
Shift
] while you move with the arrow keys to create the box.
Note that when you make a corner or intersection, the correct line characters
are exchanged for the straight line. If you make a mistake, press [
F2
] to get to
Erase mode; and then move over the unwanted line with the arrow keys while
holding [
Shift]
.
13. When you have completed the box, press [
ESC
] to exit Line-draw mode.