Difference between revisions of "ASCII"

==Context==

==Context==

*At the time this coding scheme was introduced the common teletypewriter code was Baudot, which was only 6 bits and required a shift key like that on the typewriter.

*At the time this coding scheme was introduced the common teletypewriter code was Baudot, which was only 6 bits and required a shift key like that on the typewriter.

==Problem==

==Problem==

Most of the solutions create more problems than they solve.

Most of the solutions create more problems than they solve.

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|colspan=3|DEL|| style="font-size:large;" | ␡ || <code>[[^?]]</code> || || style="text-align:left;" | [[Delete character|Delete]]{{Efn|The [[Delete character]] can sometimes be entered by pressing the {{key press|Backspace}} key on some systems.}}{{Efn|name="bsp del mismatch"|The ambiguity of [[Backspace]] is due to early terminals designed assuming the main use of the keyboard would be to manually punch paper tape while not connected to a computer. To delete the previous character, one had to back up the paper tape punch, which for mechanical and simplicity reasons was a button on the punch itself and not the keyboard, then type the rubout character. They therefore placed a key producing rubout at the location used on typewriters for backspace. When systems used these terminals and provided command-line editing, they had to use the "rubout" code to perform a backspace, and often did not interpret the backspace character (they might echo "<code>^H</code>" for backspace). Other terminals not designed for paper tape made the key at this location produce Backspace, and systems designed for these used that character to back up. Since the delete code often produced a backspace effect, this also forced terminal manufacturers to make any {{key press|Delete}} key produce something other than the Delete character.}}

|colspan=3|DEL|| style="font-size:large;" | ␡ || <code>[[^?]]</code> || || style="text-align:left;" | [[Delete character|Delete]]{{Efn|The [[Delete character]] can sometimes be entered by pressing the {{key press|Backspace}} key on some systems.}}{{Efn|name="bsp del mismatch"|The ambiguity of [[Backspace]] is due to early terminals designed assuming the main use of the keyboard would be to manually punch paper tape while not connected to a computer. To delete the previous character, one had to back up the paper tape punch, which for mechanical and simplicity reasons was a button on the punch itself and not the keyboard, then type the rubout character. They therefore placed a key producing rubout at the location used on typewriters for backspace. When systems used these terminals and provided command-line editing, they had to use the "rubout" code to perform a backspace, and often did not interpret the backspace character (they might echo "<code>^H</code>" for backspace). Other terminals not designed for paper tape made the key at this location produce Backspace, and systems designed for these used that character to back up. Since the delete code often produced a backspace effect, this also forced terminal manufacturers to make any {{key press|Delete}} key produce something other than the Delete character.}}

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==References==

==References==