Printek 4503 - Manual (Page 85)

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DEC LA120 EMULATION
Introduction
This section describes the control codes and escape sequences comprising DEC
LA120 emulation. This emulation may be selected by specifying "Mode: LA120" in
the "Setup: INTERFACE" menu, or via software with the ESC ESC 5 sequence.
While this emulation is selected, control codes and escape sequences from other
emulations are not available.
Control codes and escape sequences are used to control printer operation. An ASCII
control code is a single character in the range 00 hex through 1F hex, and 7F hex.
The ESC (Escape) control code (1B hex) is used to introduce character strings called
escape sequences, which provide an extension of the commands available with ASCII
control codes.
The LA120 control codes and escape sequences follow the standards of the ANSI
X3.64 specification. Many ANSI escape sequences begin with a two character
Control Sequence Introducer (CSI), Escape Left Square Bracket (ESC [, 1B 5B hex).
If 8-bit data is selected via control panel setup, these two characters may be replaced
by a single character CSI, 9B hex. The sequences are always documented in this
section with the two character CSI (ESC [), because this format seems to be much
more common, and works equally well with 7-bit or 8-bit data.
Some escape sequences accept one or more numeric parameters. A numeric
parameter is a decimal number represented by a string of ASCII decimal digits ("0"
through "9"). Leading zeros may be supplied, but are not necessary. Due to
implementation constraints, the largest value that can be accepted is decimal 255.
Larger values will be treated as zero. Omitting a numeric parameter is equivalent to
supplying a value of zero.
If a sequence accepts one numeric parameter, it will be represented as "n". If a
sequence accepts more than one numeric parameter, they will be represented as "n1;
n2; ... nx". Note that multiple numeric parameters are separated by a semicolon.
Most LA120 escape sequences will assume one of the following formats:
ESC f (no numeric parameters)
ESC n f (one numeric parameter)
ESC n1; n2; ... nx f (two or more numeric parameters)