N76E003之IAP

修改FLASH數據通常需要很長時間，不像RAM那樣可以實時操作。而且擦除、編程或讀取FLASH數據需要遵循相當復雜的時序步驟。N76E003提供方便FALSH編程方式，可以幫助用戶通過IAP方式，重新編程FLASH內容。IAP就是通過軟件實現在線電擦除和編程的方法。
通過設置IAPEN（CHPCON.0受TA保護）使能IAP，並且設置IAPUEN寄存器的相應位，使能需要升級的FLASH區域（CONFIG、LDROM、APROM），用戶將16位操作地址寫入IAPAH和IAPAL，數據寫入IAPFD，命令寫入IAPCN。然后通過設置觸發位IAPGO(IAPTRG.0)，去執行IAP。注意：IAPTRG也受TA保護。此時，CPU保持程序計數器，內嵌IAP自動控制內部充電泵提高電壓和信號時序。擦除和編程時間是內部控制的，與工作電壓和頻率無關。通常頁擦除時間是5ms，字節編程時間是 3.5μs。IAP動作完成后，程序計數器繼續運行之后的指令，IAPGO位將自動清零。IAPFF (CHPCON.6)是IAP錯誤標志，可以用來檢查之前IAP操作成功與否。通過這些純軟件的設置，用戶可以很方便對FLASH存儲器進行擦除、編程和校驗。

 

 

IAP可以方便用戶更新FLASH內容，不過用戶必須遵循一定規則，以確保IAP正確執行，否則可能引起不確定的結果，甚至損壞器件。此外，下文對於正確執行IAP有很好建議。
(1)沒有IAP操作時，用戶必須清IAPEN (CHPCON.0)位。可以防止系統意外觸發IAP。此外，IAP需要使用內部HIRC振盪器。如果選擇外部時鍾源，禁止IAP將停止內部HIRC，可以達到省電的目的。注：寫IAPEN受TA保護。
(2)當LOCK位(CONFIG0.1) 被激活，IAP讀、寫或擦除仍然有效。

在進行IAP時，如果中斷打開應該臨時清除EA位
擦除或編程的頁不能是當前代碼執行的頁。否則會出現不可預計程序動作，甚至破壞存儲的數據

使用flash存儲器作為數據存儲
在一般應用中，有時需要一些數據在斷電情況下不能丟失，以便用戶讀回或更新，作為系統控制的參數。N76E003支持IAP功能並且存儲在flash中的字節都可以用MOVC指令讀取，所以很適合作為非易失數據存儲器。Flash寫次數為100,000次，以下參考應用代碼：

匯編例程如下:
;******************************************************************************
; This code illustrates how to use IAP to make APROM 201h as a byte of
; Data Flash when user code is executed in APROM.
;******************************************************************************
PAGE_ERASE_AP EQU 00100010b
BYTE_PROGRAM_AP EQU 00100001b
ORG 0000h
MOV TA,#0Aah ;CHPCON is TA protected
MOV TA,#55h
ORL CHPCON,#00000001b ;IAPEN = 1, enable IAP mode
MOV TA,#0Aah ;IAPUEN is TA protected
MOV TA,#55h
ORL IAPUEN,#00000001b ;APUEN = 1, enable APROM update
MOV IAPCN,#PAGE_ERASE_AP ;Erase page 200h~27Fh
MOV IAPAH,#02h
MOV IAPAL,#00h
MOV IAPFD,#0FFh
MOV TA,#0Aah ;IAPTRG is TA protected
MOV TA,#55h
ORL IAPTRG,#00000001b ;write ‘1’ to IAPGO to trigger IAP process
MOV IAPCN,#BYTE_PROGRAM_AP ;Program 201h with 55h
MOV IAPAH,#02h
MOV IAPAL,#01h
MOV IAPFD,#55h

MOV TA,#0Aah
MOV TA,#55h
ORL IAPTRG,#00000001b
MOV TA,#0Aah
MOV TA,#55h
ANL IAPUEN,#11111110b ;APUEN = 0, disable APROM update
MOV TA,#0Aah
MOV TA,#55h
ANL CHPCON,#11111110b ;IAPEN = 0, disable IAP mode
MOV DPTR,#201h
CLR A
MOVC A,@A+DPTR ;Read content of address 201h
MOV P0,A
SJMP $

C 語言例程如下:
//******************************************************************************
// This code illustrates how to use IAP to make APROM 201h as a byte of
// Data Flash when user code is executed in APROM.
//******************************************************************************
#define PAGE_ERASE_AP 0x22
#define BYTE_PROGRAM_AP 0x21
/*Data Flash, as part of APROM, is read by MOVC. Data Flash can be defined as
128-element array in “code” area from absolute address 0x0200 */
volatile unsigned char code Data_Flash[128] _at_ 0x0200;
Main (void)
{
TA = 0xAA; //CHPCON is TA protected
TA = 0x55;
CHPCON |= 0x01; //IAPEN = 1, enable IAP mode
TA = 0xAA; //IAPUEN is TA protected
TA = 0x55;
IAPUEN |= 0x01; //APUEN = 1, enable APROM update
IAPCN = PAGE_ERASE_AP; //Erase page 200h~27Fh
IAPAH = 0x02;
IAPAL = 0x00;
IAPFD = 0xFF;
TA = 0xAA; //IAPTRG is TA protected
TA = 0x55;
IAPTRG |= 0x01; //write ‘1’ to IAPGO to trigger IAP process
IAPCN = BYTE_PROGRAM_AP; // Program 201h with 55h
IAPAH = 0x02;
IAPAL = 0x01;

IAPFD = 0x55;

TA = 0xAA;
TA = 0x55;
IAPTRG |= 0x01; //write ‘1’ to IAPGO to trigger IAP process
TA = 0xAA; //IAPUEN is TA protected
TA = 0x55;
IAPUEN &= ~0x01; //APUEN = 0, disable APROM update
TA = 0xAA; //CHPCON is TA protected
TA = 0x55;
CHPCON &= ~0x01; //IAPEN = 0, disable IAP mode
P0 = Data_Flash[1]; //Read content of address 200h+1
while(1);
}

 N76E003 APROM程序DATAFLASH為EEPROM方式

#include <stdio.h>
#include "N76E003.h"
#include "Common.h"
#include "Delay.h"
#include "SFR_Macro.h"
#include "Function_Define.h"

bit BIT_TMP;

//-------------------------------------------------------------------------
UINT8 read_APROM_BYTE(UINT16 code *u16_addr)
{
    UINT8 rdata;
    rdata = *u16_addr>>8;
    return rdata;
}
//-------------------------------------------------------------------------


/*****************************************************************************************************************
write_DATAFLASH_BYTE :
user can copy all this subroutine into project, then call this function in main.
******************************************************************************************************************/        
void write_DATAFLASH_BYTE(UINT16 u16_addr,UINT8 u8_data)
{
    UINT8 looptmp=0,u8_addrl_r;
    unsigned char code *cd_longaddr;
    unsigned char xdata *xd_tmp;
    
//Check page start address
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r = 0;
    }
    else 
    {
        u8_addrl_r = 0x80;
    }
//Save APROM data to XRAM
    xd_tmp = 0x80;
    cd_longaddr = (u16_addr&0xff00)+u8_addrl_r;    
    while (xd_tmp !=0x100)
    {
        *xd_tmp = *cd_longaddr;
        looptmp++;
        xd_tmp++;
        cd_longaddr++;
    }
// Modify customer data in XRAM
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        xd_tmp = u8_addrl_r+0x80;
    }
    else
    {
        xd_tmp = u8_addrl_r+0;
    }
    *xd_tmp = u8_data;
//Erase APROM DATAFLASH page
        IAPAL = u16_addr;
        IAPAH = u16_addr>>8;
        IAPFD = 0xFF;
      set_IAPEN; 
        set_APUEN;
    IAPCN = 0x22;         
         set_IAPGO; 
//Save changed RAM data to APROM DATAFLASH
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r =0;
    }
    else
    {
        u8_addrl_r = 0x80;
    }
        xd_tmp = 0x80;
      IAPAL = u8_addrl_r;
    IAPAH = u16_addr>>8;
        set_IAPEN; 
        set_APUEN;
      IAPCN = 0x21;
        while (xd_tmp !=0xFF)
        {
            IAPFD = *xd_tmp;
            set_IAPGO;
            IAPAL++;
            xd_tmp++;
        }
        clr_APUEN;
        clr_IAPEN;
}    
/******************************************************************************************************************/        


void main (void) 
{
        UINT8 datatemp;
/* -------------------------------------------------------------------------*/
/*  Dataflash use APROM area                                                                         */
/*    APROM 0x3800~0x38FF demo as dataflash                                                         */
/* Please use Memory window key in C:0x3800 to check earse result                      */          
/* -------------------------------------------------------------------------*/
    
//call write byte 
        write_DATAFLASH_BYTE (0x3881,0x55);
        write_DATAFLASH_BYTE (0x3882,0x56);
        write_DATAFLASH_BYTE (0x3855,0xaa);
        write_DATAFLASH_BYTE (0x3856,0x66);
//call read byte
        datatemp = read_APROM_BYTE(0x3882);
    while(1);
}

下面針對每一個調用函數進行講解

void write_DATAFLASH_BYTE(UINT16 u16_addr,UINT8 u8_data)
{
    UINT8 looptmp=0,u8_addrl_r;
    unsigned char code *cd_longaddr;
    unsigned char xdata *xd_tmp;
    
//Check page start address
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r = 0;
    }
    else 
    {
        u8_addrl_r = 0x80;
    }
//Save APROM data to XRAM
    xd_tmp = 0x80;
    cd_longaddr = (u16_addr&0xff00)+u8_addrl_r;    
    while (xd_tmp !=0x100)
    {
        *xd_tmp = *cd_longaddr;
        looptmp++;
        xd_tmp++;
        cd_longaddr++;
    }
// Modify customer data in XRAM
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        xd_tmp = u8_addrl_r+0x80;
    }
    else
    {
        xd_tmp = u8_addrl_r+0;
    }
    *xd_tmp = u8_data;
//Erase APROM DATAFLASH page
        IAPAL = u16_addr;
        IAPAH = u16_addr>>8;
        IAPFD = 0xFF;
        set_IAPEN; 
        set_APUEN;
    IAPCN = 0x22;         
         set_IAPGO; 
//Save changed RAM data to APROM DATAFLASH
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r =0;
    }
    else
    {
        u8_addrl_r = 0x80;
    }
        xd_tmp = 0x80;
      IAPAL = u8_addrl_r;
    IAPAH = u16_addr>>8;
        set_IAPEN; 
        set_APUEN;
      IAPCN = 0x21;
        while (xd_tmp !=0xFF)
        {
            IAPFD = *xd_tmp;
            set_IAPGO;
            IAPAL++;
            xd_tmp++;
        }
        clr_APUEN;
        clr_IAPEN;
}    

上面這個函數，是對DATAFLASH  EEPROM進行讀寫，有主函數給出地址和數據，由該函數進行處理

void write_DATAFLASH_BYTE(UINT16 u16_addr,UINT8 u8_data)
{
    UINT8 looptmp=0,u8_addrl_r;
    unsigned char code *cd_longaddr;
    unsigned char xdata *xd_tmp;
    
//Check page start address
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r = 0;
    }
    else 
    {
        u8_addrl_r = 0x80;
    }
//Save APROM data to XRAM
    xd_tmp = 0x80;
 cd_longaddr = (u16_addr&0xff00)+u8_addrl_r;    
    while (xd_tmp !=0x100)
    {
        *xd_tmp = *cd_longaddr;         looptmp++;
        xd_tmp++;
        cd_longaddr++;
    }
// Modify customer data in XRAM
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        xd_tmp = u8_addrl_r+0x80;
    }
    else
    {
        xd_tmp = u8_addrl_r+0;
    }
    *xd_tmp = u8_data;
//Erase APROM DATAFLASH page
        IAPAL = u16_addr;
        IAPAH = u16_addr>>8;
        IAPFD = 0xFF;
        set_IAPEN; 
        set_APUEN;
    IAPCN = 0x22;         
         set_IAPGO; 
//Save changed RAM data to APROM DATAFLASH
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r =0;
    }
    else
    {
        u8_addrl_r = 0x80;
    }
        xd_tmp = 0x80;
      IAPAL = u8_addrl_r;
    IAPAH = u16_addr>>8;
        set_IAPEN; 
        set_APUEN;
      IAPCN = 0x21;
        while (xd_tmp !=0xFF)
        {
            IAPFD = *xd_tmp;
            set_IAPGO;
            IAPAL++;
            xd_tmp++;
        }
        clr_APUEN;
        clr_IAPEN;
}    

標紅部分涉及到兩個寄存器IAPL與IAPH，這起什么作用呢？看一下手冊

由此可知，這兩個寄存器是寫入16位地址字節的，也就是說u8_addrl_r這個變量的含義是給寄存器提供地址，因此，需要一些數據的分析和處理，

 u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r = 0;
    }
    else 
    {
        u8_addrl_r = 0x80;
    }
//Save APROM data to XRAM
    xd_tmp = 0x80;
    cd_longaddr = (u16_addr&0xff00)+u8_addrl_r;    
    while (xd_tmp !=0x100) { *xd_tmp = *cd_longaddr; looptmp++; xd_tmp++; cd_longaddr++; }

Save APROM data to XRAM

首先查看N76E003的數據手冊得知這顆芯片的XRAM的大小為：768字節i ，即大小為0x300，另外還可知道Flash每一頁的大小為128字節即0x80。這段歷程划分區域到0X100（256）。

 

 

// Modify customer data in XRAM
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        xd_tmp = u8_addrl_r+0x80;
    }
    else
    {
        xd_tmp = u8_addrl_r+0;
    }
    *xd_tmp = u8_data;
//Erase APROM DATAFLASH page
        IAPAL = u16_addr;
        IAPAH = u16_addr>>8;
        IAPFD = 0xFF;
        set_IAPEN; 
        set_APUEN;
    IAPCN = 0x22;         
         set_IAPGO; 

 

 Modify customer data in XRAM
 在XRAM中修改客戶數據

 

 

 

 

//Save changed RAM data to APROM DATAFLASH
    u8_addrl_r = u16_addr;
    if (u8_addrl_r<0x80)
    {
        u8_addrl_r =0;
    }
    else
    {
        u8_addrl_r = 0x80;
    }
        xd_tmp = 0x80;
      IAPAL = u8_addrl_r;
      IAPAH = u16_addr>>8;
        set_IAPEN; 
        set_APUEN;
      IAPCN = 0x21;
        while (xd_tmp !=0xFF)
        {
            IAPFD = *xd_tmp;
            set_IAPGO;
            IAPAL++;
            xd_tmp++;
        }
        clr_APUEN;
        clr_IAPEN;
}    

這部分比較復雜，我后續會有更新，如果有什么意見或建議，歡迎評論

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