Browse Prior Art Database

Host Emulated Printer, Backspace User Interface

IP.com Disclosure Number: IPCOM000103528D
Original Publication Date: 1990-Dec-01
Included in the Prior Art Database: 2005-Mar-18
Document File: 1 page(s) / 36K

Publishing Venue

IBM

Related People

Cheatheam Jr, LD: AUTHOR

Abstract

Disclosed is a user interface for selecting a host-emulated printer backspace algorithm in a computer program.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Host Emulated Printer, Backspace User Interface

      Disclosed is a user interface for selecting a host-emulated
printer backspace algorithm in a computer program.

      Two algorithms for handling a backspace in a printer datastream
are supported.  The first is used with printers that do not support a
backspace command.  Each host backspace command is converted to a
carriage return and enough spaces to move the print head to the
character that was processed immediately before the backspace.  The
number of spaces output is decremented for each contiguous backspace
so that the print head is moved one less character for each
backspace.  Because of memory constraints, the number of contiguous
sets of backspaces per line is limited.

      The second algorithm is for printers that do support a
backspace command. Each host backspace command is converted to the
printer backspace command.

      Since the capabilities of the printer are unknown to the
computer program, the user can specify which algorithm to use.  This
is done with an item on a menu:
  Printer Backspace     2       1=Yes     2=No

      The default is for the first algorithm that does not support
printer backspace.

      Anonymous.