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Line Drawing Characters

Line drawing can create simple graphics on character-mode terminals and printers. There are three common, incompatible, character sets: HP, ANSI/VT, and ECS/PC-8.

The terminals turn on line drawing using the Shift-Out Character (^N, $0e) and cancel it with Shift-In (^O, $0f). For detailed reference manuals on HP and DEC terminals, visit the WRQ Support web page.

To use ^N on a VT terminal, select "Special Graphics Character Set" as set G1 with Esc5)0. The ANSI/VT codes are also the default line-drawing codes for versions of UNIX which support them.

On the original IBM PC, the ECS Extended Character Set defined line drawing graphics for some of the upper 128 character codes. Therefore you didn't need to use Shift-In and Shift-Out.

However, Windows uses the ANSI extended character set, which is based on ISO Latin-1. This means Windows handles more European languages, but has no line-drawing symbols.

On an HP Laserjet, you can use the PC-8 symbol set if you want ECS. Select PC-8 for the primary LaserJet font with Esc5(10UEsc5(s0P, then enter character values between 179 and 254 ($b3 - $fe).

Here are the only line drawing symbols which are common to all three character sets:

Text version

Upper left cornerrlda
Upper right cornertkbf
Lower left cornerfmc0
Lower right cornergj d9
Horizontal line,qc4
Vertical line.xb3
Cross center lines /nc5
Right tee6ub4
Left tee5tc3
Bottom tee8vc1
Top tee7wc2

To enter characters which don't appear on the keyboard, see Extended Characters.

You can also draw forms on HP terminals using Display Enhancements.

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