Intermec 6820 Series, User Manual

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Control Code Definitions Chapter
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64 6820 Series 80-Column Printer User’s Manual
Control Code Definitions
I/O Buffer
All characters and control codes received by the printer are stored in this
buffer. Characters and controls codes are read from this buffer and acted
upon to form the print buffer. Characters are removed from the I/O buffer
as they are processed.
Print (image) Buffer
All characters go through this buffer on their way to the printed page. This
buffer contains the graphic image of the dots to print, from which charac-
ters are rendered. It is cleared when its contents are printed.
Special Notations
The following information defines notations included in the format defini-
tions of the escape sequences, throughout this section.
Notation Description
(0) Used in the
ASCII
column of any of the Format definitions, indicates that its value can only be zero
(and not the character “0”). For example: Select Top-Down Printing ESC US (0).
(1) Used in the
ASCII
column of any of the Format definitions, indicates that its value can only be one
(and not the character “1”). For example: Select Bottom-Up Printing ESC US (1).
* When a number (at the end of an escape sequence) is marked with an asterisk, then either the value
corresponding to that number or the value of the string character can be used for that number.
For example, if 1* is shown, then either the value (1), or the value of the string character (decimal:
49, hex: 31) can be used.
NUL
T
he NUL character is represented in the Dec column as 0, in the Hex column as 00, and in the
ASCII column as NUL.
General Printer Control Functions
Backspace
The print buffer is emptied. The print head is moved to the left one char-
acter space (using the current pitch). This can be performed to, but not
beyond, the left margin setting. The backspace is ignored if justification of
right, full, or centered is selected.
Format
Decimal Hex ASCII
8 08 BS
The backspace control code (BS) is not reliable when text contains differ-
ent character pitches. For reliable backspacing, use the escape sequence
(ESC “\”),
Set Relative Print Position .