Intermec VT220/ANSI, Programmer'S Reference Manual

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SECTION 8
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Programming
8-2 VT220/ANSI Terminal Emulation Programmer’s Reference Guide
Character Encoding
The implementation of VT220/ANSI terminal emulation
supports both 7-bit and 8-bit communications environ-
ments. The implementation consists of an 8-bit asynchro-
nous character encoding scheme and a 7-bit code extension
technique so that the wireless station is compatible with
ANSI and ISO standards. All 8-bit codes can be referenced
by using two-byte ESCape sequences in accordance with
ANSI standard X3.41 ---- 1974.
The document commonly referred to when ANSI is men-
tioned is ANSI X3.64 ---- 1979, Additional Controls for Use
With American National Standard for Information Inter-
change. The ANSI X3.64 standard controls character imag-
ing devices like the VT220. ANSI and ISO determine the
current standards for character encoding in the communica-
tions industry.
Character Sets
The wireless station processes most characters it receives
from the host computer based on characters whose codes
and functions are defined and standardized by ANSI. The
types are 7-bit and 8-bit character codes.
Multinational Character Set
The DEC multinational character set consists of C0, GL,
C1, and GR codes.