25 lines
454 B
C
25 lines
454 B
C
#include <internals/keyboard.h>
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/*
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getPressedKey()
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Finds a pressed key in the keyboard state and returns it.
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*/
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int getPressedKey(volatile unsigned char *keyboard_state)
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{
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int row = 1, column = 0;
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int state;
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if(keyboard_state[0] & 1) return KEY_AC_ON;
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while(row <= 9 && !keyboard_state[row]) row++;
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if(row > 9) return KEY_NONE;
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state = keyboard_state[row];
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while(!(state & 1))
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{
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state >>= 1;
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column++;
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}
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return (column << 4) | row;
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}
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