kboard.c

这是我做项目时的一个NX25P40(FLASH)芯片测试程序。相信对做单片机开发需要大容量FLASH的朋友有帮助。该测试程序采用keil51开发

#include "Kboard.h"
#include "reg52.h"
#include "stdio.h"
#include "51LIB.h"
static const unsigned char code KEY_IO[16] = {0x77, 0xB7, 0xD7, 0xE7,
                                              0x7B, 0xBB, 0xDB, 0xEB,
                                              0x7D, 0xBD, 0xDD, 0xED,
                                              0x7E, 0xBE, 0xDE, 0xEE};
static const char code KEY_MAP[16] = {'2', '1', '3', 'A',
                                      '5', '4', '6', 'B',
                                      '8', '7', '9', '\r',
                                      '0', 'P', 'C', '\b'}; 
static unsigned char kboard_makekey(void);
static void kboard_breakkey(void);
static unsigned char kboard_idkey(void);

static unsigned char kboard_makekey(void)
{
    unsigned char key, newkey;

    do
    {
        while((key = kboard_idkey()) == NOKEY);
        delay_ms(10);
    } while((newkey = kboard_idkey()) != key);

    return(key);
}
static void kboard_breakkey(void)
{
    do
    {
        while(kboard_idkey() != NOKEY);
        delay_ms(10);
    } while(kboard_idkey() != NOKEY);
}
static unsigned char kboard_idkey(void)
{
    unsigned char key = 0xFF;
    bit keyfound = 0;

    do
    {
        key++;
        KEYPORT &= 0xF0;                
        KEYPORT |= KEY_IO[key] & 0x0F;  
        keyfound = ((KEYPORT & 0xF0) == (KEY_IO[key] & 0xF0));
        
    } while((key < NOKEY) && (!keyfound));

    return(key);    
}
void kboard_init(void)
{
    KEYPORT = 0xFF;     
}
char get_key(void)
{   unsigned char key;
    KEYPORT=0xf0;
	key=KEYPORT;
	if(key==0xf0) return 0;
	printf("key is %#x\r\n",(unsigned int)key);
	key=NOKEY;
	while(key==NOKEY)
	    {key = kboard_makekey();
		 printf("Wait release!\r\n");
         kboard_breakkey();
	    }
	return KEY_MAP[key];
}