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What is the name of the back arrow key on top left corner of the C64 Keyboard?

Is it escape or back? Also I don't recall using this key. What was the intended usage of it?

Commodore64 Keyboard Layout?

  • DOS Wedge used it early on as shorthand for SAVE. Other DOS wedges, like JiffyDOS, copies this. That's the only consistent usage I've seen. – Brian H Mar 22 '17 at 22:17
  • Was used to load Turbo :)... <---L – Vedran Maricevic. Jun 6 '17 at 15:55
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According to this source, which seems to have been written with visibility of ANSI X3.4-1963, the original ASCII standard, it's simply "a left-pointing arrow. This character was used as an assignment operator in some programming languages."

The character lives on in unicode as U+2190 where it has the formal name "LEFTWARDS ARROW".

It's unlikely to have been an influence on Commodore, but ← continued to serve as an assignment operator at least as late as Smalltalk-80:

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  • 1
    In the Smalltalk (your example) language (created at Xerox Labs around 1970 and using their keyboards) "<-" was used for assignment - and it actually produced an arrow. Today the corresponding key is the "_" (underscore) key. So x <- 2 + 2 would be typed and shown as x _ 2 + 2. It's now recommended to use := (ie. : followed by =) as assignement-operator (like in Pascal) instead. The up-arrow was used for "return a value from function", and has been replaced - both key and font - with the ^ in Smalltalk. Not sure how this related/worked with C64 though... – Baard Kopperud Mar 22 '17 at 21:19
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It actually typed a left-pointing arrow. It's from an early version of ASCII (1963 rather than the "modern" 1967 version) that was used for the basis of PETSCII; in the 1967 version of ASCII we know and love today, this character was replaced with an underscore. I don't recall if it has a name; it's probably just "left-arrow" or something.

  • I suspect the glyph was chosen for position 0x5F because many devices would map codes 0x60-0x7F to 0x40-0x5F, and 0x7F was rubout. Note that that wasn't a "command" to rub something out, but rather an indication that something had been rubbed out (e.g. by overpunching all the holes). Someone reading a printout with a back-arrow could realize that he character to the right should appear where the arrow does. – supercat Mar 5 '18 at 3:16
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I only recall it as being referred to as 'left arrow' but I think it also had a function when used with the Control key, as some of the other keys did. For example in programming you might type: PRINT "Q" (was that the clear screen command, does anyone remember?) or PRINT " <-" There were different CTRL- combinations that moved the cursor around, cleared the screen and so on...

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