55 lines
863 B
C
55 lines
863 B
C
#include <internals/keyboard.h>
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/*
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getPressedKeys()
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Find 'count' pressed keys in the keyboard state and fills the 'keys'
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array. Returns the number of actually-pressed keys found.
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*/
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int getPressedKeys(volatile unsigned char *keyboard_state, int *keys,
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int count)
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{
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int row = 1, column;
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int found = 0, actually_pressed;
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int state;
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if(count <= 0) return 0;
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if(keyboard_state[0] & 1)
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{
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keys[found++] = KEY_AC_ON;
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count--;
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}
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while(count && row <= 9)
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{
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while(row <= 9 && !keyboard_state[row]) row++;
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if(row > 9) break;
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state = keyboard_state[row];
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column = 0;
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while(count && column < 8)
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{
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if(state & 1)
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{
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keys[found++] = (column << 4) | row;
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count--;
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}
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state >>= 1;
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column++;
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}
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row++;
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}
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actually_pressed = found;
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while(count)
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{
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keys[found++] = KEY_NONE;
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count--;
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}
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return actually_pressed;
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}
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