Browse Prior Art Database

Auto-Erase Compatibility With Memory Storage Logic In Typewriters

IP.com Disclosure Number: IPCOM000048825D
Original Publication Date: 1982-Mar-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 5 page(s) / 56K

Publishing Venue

IBM

Related People

Hallman, BL: AUTHOR [+3]

Abstract

The scheme set forth herein improves the human factor aspects associated with an auto-erase function in a typewriter. Without requiring special user instructions, the logic described always enables the carrier to provide the reference point for linking a typewritten entry position with its counterpart in line memory. Moreover, it is possible to overstrike a printed image (s) and have the constructed graphic addressed by an auto-erase operation.

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Auto-Erase Compatibility With Memory Storage Logic In Typewriters

The scheme set forth herein improves the human factor aspects associated with an auto-erase function in a typewriter. Without requiring special user instructions, the logic described always enables the carrier to provide the reference point for linking a typewritten entry position with its counterpart in line memory. Moreover, it is possible to overstrike a printed image (s) and have the constructed graphic addressed by an auto-erase operation.

In a typewriter with a moving carrier and at least a one line memory, the carrier's position with respect to its print point location should always be in "sync" with that being recorded in memory. The intent is to enable the carrier to act in a manner somewhat akin to a cursor on a CRT display. In so doing, the real purpose will have been achieved, that is, to provide the typist with the conception that the imaged copy, as well as the carrier's location, is identical to that which is in the memory storage file.

This is not the case with certain typewriters. For example the coded backspace or nonerase key operation enables the carrier to move from right to left without erasing the hard copy. It should be realized, however, that this coded operation is stored in a sequential fashion in the line memory and does not relate to the position of the carrier. Thus, if an auto-erase operation of a print image is subsequently desired at the carrier's repositioned location, it cannot be induced because the auto-erase key operation will "play out" the preceding operations recorded in memory which, in the case of the coded backspace entries, will cause the carrier to move in the reverse direction or from left to right

Other typewriters function differently than the above-described model, but they also may be confusing to the neophyte. For example, the coded backspace or nonerase key operation also enables the carrier to move from right to left but, unlike the above-described model, these backspacing operations are not stored in memory. Therefore, the data recorded on the copy at the carrier's repositioned location remains in sync or is the same as that recorded in the line memory logic for that specific location, and an appropriate auto-erase operation can take, place if initiated. However, the problem associated with the latter model typewriter operation presents itself after the correction has been made. If the space bar function is used to move the carrier back to the right, or its starting, position prior to the coded backspace operations, the (space codes) supersede or replace those previously entered codes which reflect what has already been printed on the copy. Thus, the stored memory no longer duplicates what is observed and/or depicted on the typewritten line.

It was previously stated that the intent of this scheme is to enable the carrier to act in a manner somewhat akin to a cursor on a CRT display. Of course, this cannot be imp...