STC12C5A系列单片机内部 EEPROM 的应用
参考范例程序。
eeprom.c
#include "eeprom.h"/*----------------------------
Disable ISP/IAP/EEPROM function
Make MCU in a safe state
----------------------------*/
void IapIdle()
{IAP_CONTR = 0; //Close IAP functionIAP_CMD = 0; //Clear command to standbyIAP_TRIG = 0; //Clear trigger registerIAP_ADDRH = 0x80; //Data ptr point to non-EEPROM areaIAP_ADDRL = 0; //Clear IAP address to prevent misuse
}/*----------------------------
Read one byte from ISP/IAP/EEPROM area
Input: addr (ISP/IAP/EEPROM address)
Output:Flash data
----------------------------*/
BYTE IapReadByte(WORD addr)
{BYTE dat; //Data bufferIAP_CONTR = ENABLE_IAP; //Open IAP function, and set wait timeIAP_CMD = CMD_READ; //Set ISP/IAP/EEPROM READ commandIAP_ADDRL = addr; //Set ISP/IAP/EEPROM address lowIAP_ADDRH = addr >> 8; //Set ISP/IAP/EEPROM address highIAP_TRIG = 0x5a; //Send trigger command1 (0x5a)IAP_TRIG = 0xa5; //Send trigger command2 (0xa5)_nop_(); //MCU will hold here until ISP/IAP/EEPROM operation completedat = IAP_DATA; //Read ISP/IAP/EEPROM dataIapIdle(); //Close ISP/IAP/EEPROM functionreturn dat; //Return Flash data
}/*----------------------------
Program one byte to ISP/IAP/EEPROM area
Input: addr (ISP/IAP/EEPROM address)dat (ISP/IAP/EEPROM data)
Output:-
----------------------------*/
void IapProgramByte(WORD addr, BYTE dat)
{IAP_CONTR = ENABLE_IAP; //Open IAP function, and set wait timeIAP_CMD = CMD_PROGRAM; //Set ISP/IAP/EEPROM PROGRAM commandIAP_ADDRL = addr; //Set ISP/IAP/EEPROM address lowIAP_ADDRH = addr >> 8; //Set ISP/IAP/EEPROM address highIAP_DATA = dat; //Write ISP/IAP/EEPROM dataIAP_TRIG = 0x5a; //Send trigger command1 (0x5a)IAP_TRIG = 0xa5; //Send trigger command2 (0xa5)_nop_(); //MCU will hold here until ISP/IAP/EEPROM operation completeIapIdle();
}/*----------------------------
Erase one sector area
Input: addr (ISP/IAP/EEPROM address)
Output:-
----------------------------*/
void IapEraseSector(WORD addr)
{IAP_CONTR = ENABLE_IAP; //Open IAP function, and set wait timeIAP_CMD = CMD_ERASE; //Set ISP/IAP/EEPROM ERASE commandIAP_ADDRL = addr; //Set ISP/IAP/EEPROM address lowIAP_ADDRH = addr >> 8; //Set ISP/IAP/EEPROM address highIAP_TRIG = 0x5a; //Send trigger command1 (0x5a)IAP_TRIG = 0xa5; //Send trigger command2 (0xa5)_nop_(); //MCU will hold here until ISP/IAP/EEPROM operation completeIapIdle();
}eeprom.h
#ifndef _EEPROM_H_
#define _EEPROM_H_#include "stc12c5a60s2.h"
#include "intrins.h"typedef unsigned char BYTE;
typedef unsigned int WORD;/*Define ISP/IAP/EEPROM command*/
#define CMD_IDLE 0 //Stand-By
#define CMD_READ 1 //Byte-Read
#define CMD_PROGRAM 2 //Byte-Program
#define CMD_ERASE 3 //Sector-Erase/*Define ISP/IAP/EEPROM operation const for IAP_CONTR*/
#define ENABLE_IAP 0x83 //if SYSCLK<12MHz//Start address for STC12C5A60S2 EEPROM - 两个扇区
#define IAP_ADDRESS 0x0000 // 第一扇区
#define IAP_SECOND_ADDRESS 0x0200 // 第二扇区// 函数声明
extern BYTE IapReadByte(WORD addr);
extern void IapProgramByte(WORD addr, BYTE dat);
extern void IapEraseSector(WORD addr);#endif
STC12C5A60S2 只有两个扇区，每个扇区有 512 个字节。
测试读取功能：
dat = IapReadByte(IAP_ADDRESS);
dat2 = IapReadByte(IAP_ADDRESS+0x0001);
printf("dat = %bx , dat2 = %bx.\r\n",dat, dat2); // 若以十进制形式读取用 %bu , 若以十六进制则 %bx
测试写入功能：
IapProgramByte(IAP_ADDRESS,0x32);
IapProgramByte(IAP_ADDRESS+0x0001, 0x52);
dat = IapReadByte(IAP_ADDRESS);
dat2 = IapReadByte(IAP_ADDRESS+0x0001);
printf("dat = %bx , dat2 = %bx.\r\n",dat, dat2);
测试擦除功能：
注意：如果擦除将擦除整个扇区。
IapEraseSector(IAP_ADDRESS);
dat = IapReadByte(IAP_ADDRESS);
dat2 = IapReadByte(IAP_ADDRESS+0x0001);
printf("dat = %bx , dat2 = %bx.\r\n",dat, dat2);
运行结果如下：
