keymatrix.h

一个按件扫描程序

//************************************************
//* Matrix keyboard decoder
//* Main driver header file
//*
//* Filename:	keymatrix.h
//* Version:	1.0
//*
//* Device:		ATmega162
//* Clock:		Internal 8.000 MHz RC oscillator
//*
//************************************************
#ifndef KEYMATRIX_H
#define KEYMATRIX_H


#ifdef ALTKEYS
#include "keyaltdefs.h"							// Include alternation key definitions
#endif											// if feature is implemented


union _key_code
{
	//*
	//* Examples on use of this scan result structure
	//*
	//* key_code.complete	- Get complete 16 bit result
	//* key_code.flags		- Get flags only, include update flag
	//* key_code.altKey1	- Get flag for alternation (one-shot) key 1
	//* key_code.lckKey2	- Get flag for lock key 2
	//* key_code.updated	- Get update flag
	//* key_code.scan		- Get scancode only
	//* key_code.row		- Get row part of scancode
	//* key_code.col		- Get column part of scancode
	//*


	unsigned int complete;						// Access all 16 bits
	
	struct
	{
		union
		{
			unsigned char flags;				// Access flag status only
			
			struct
			{
				unsigned char altKey0 : 1;		// Access the flags separately
				unsigned char altKey1 : 1;
				unsigned char altKey2 : 1;
				unsigned char altKey3 : 1;
				unsigned char lckKey0 : 1;
				unsigned char lckKey1 : 1;
				unsigned char lckKey2 : 1;
				
				unsigned char updated : 1;		// Access updateflag
			};
		};
		
		union
		{
			unsigned char scan;					// Access scancode
			
			struct
			{
				unsigned char col : 3;			// Access column of keypress
				unsigned char row : 3;			// Access row of keypress
				
				unsigned char unused : 2;
			};
		};
	};
};



extern volatile union _key_code key_code;		// Scan result structure
extern volatile unsigned char key_altState;		// Current alternation flags



void key_init();								// Driver initialization
void key_stop();								// Temporary driver disable
unsigned char key_get();						// Wait for a keypress


#endif