Intermec VT220/ANSI, Programmer'S Reference Manual

Page: 186 / 276

SECTION 8
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Programming
8-50 VT220/ANSI Terminal Emulation Programmer’s Reference Guide
Control Functions
In editing mode you can use the erasure, deletion, and
insertion control functions. The character protection field
lets you design text forms that cannot be changed or over-
written. In edit mode, character protection also depends on
the setting of erasure mode (ERM):
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If ERM is set all characters can be changed, erased,
and moved, regardless of protection.
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If ERM is reset only unprotected characters can be
changed, erased, and moved. These control functions
will not affect protected areas in page memory:
Insert line (IL)
Delete line (DL)
Insert character (ICH)
Delete character (DCH)
Erase in display (ED)
Erase in line (EL)
Erase character (ECH)
Text Forms
When using C1 control characters SPA, EPA, SSA, and ESA
to create forms on the host, the rows and columns to which
the cursor moves must be in sequential order. The follow-
ing example shows some sequences that create a text form.