2020-05-09 11:55:58 -04:00
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Keyboard driver
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2020-05-12 12:41:47 -04:00
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Load range: 566-570
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2020-05-09 11:55:58 -04:00
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Implement a (key) word that interpret keystrokes from the
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builtin keyboard. The word waits for a digit to be pressed and
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returns the corresponding ASCII value.
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This routine waits for a key to be pressed, but before that, it
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waits for all keys to be de-pressed. It does that to ensure
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that two calls to _wait only go through after two actual key
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presses (otherwise, the user doesn't have enough time to
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de-press the button before the next _wait routine registers the
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same key press as a second one).
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(cont.)
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