#include <reg51.H>
#include <intrins.H>

typedef unsigned char  INT8U;
typedef unsigned int   INT16U;

sfr IAP_DATA    = 0xC2;
sfr IAP_ADDRH   = 0xC3;
sfr IAP_ADDRL   = 0xC4;
sfr IAP_CMD     = 0xC5;
sfr IAP_TRIG    = 0xC6;
sfr IAP_CONTR   = 0xC7;

//#define ENABLE_ISP 0x80               //if SYSCLK<30MHz
//#define ENABLE_ISP 0x81               //if SYSCLK<24MHz
//#define ENABLE_ISP  0x82                //if SYSCLK<20MHz
#define ENABLE_ISP 0x83               //if SYSCLK<12MHz
//#define ENABLE_ISP 0x84               //if SYSCLK<6MHz
//#define ENABLE_ISP 0x85               //if SYSCLK<3MHz
//#define ENABLE_ISP 0x86               //if SYSCLK<2MHz
//#define ENABLE_ISP 0x87               //if SYSCLK<1MHz



union union_temp16
{
    INT16U un_temp16;
    INT8U  un_temp8[2];
}my_unTemp16;

void IAP_Disable()
{
    IAP_CONTR = 0;
    IAP_CMD   = 0;
    IAP_TRIG  = 0;
    IAP_ADDRH = 0;
    IAP_ADDRL = 0;
}


INT8U eeprom_read(INT16U add)
{
    IAP_DATA = 0x00;
    IAP_CONTR = ENABLE_ISP;
    IAP_CMD = 0x01;

    my_unTemp16.un_temp16 = add;
    IAP_ADDRH = my_unTemp16.un_temp8[0];
    IAP_ADDRL = my_unTemp16.un_temp8[1];

    IAP_TRIG = 0x5A;
    IAP_TRIG = 0xA5;
    _nop_();
    IAP_Disable();

    return (IAP_DATA);
}

void eeprom_write(INT16U add, INT8U ch)
{
    IAP_CONTR = ENABLE_ISP;
    IAP_CMD = 0x02;

    my_unTemp16.un_temp16 = add;
    IAP_ADDRH = my_unTemp16.un_temp8[0];
    IAP_ADDRL = my_unTemp16.un_temp8[1];

    IAP_DATA = ch;
    //EA = 0;
    IAP_TRIG = 0x5A;
    IAP_TRIG = 0xA5;
    _nop_();
    //EA = 1;
    IAP_Disable();

}

void eeprom_erase(INT16U add)
{
    IAP_CONTR = ENABLE_ISP;
    IAP_CMD = 0x03;

    my_unTemp16.un_temp16 = add;
    IAP_ADDRH = my_unTemp16.un_temp8[0];
    IAP_ADDRL = my_unTemp16.un_temp8[1];

    //EA = 0;
    IAP_TRIG = 0x5A;
    IAP_TRIG = 0xA5;
    _nop_();
    _nop_();
    _nop_();
    //EA = 1;
    IAP_Disable();

}


#include "reg51.h"
#define BAUD  0xF400                  // 1200bps @ 11.0592MHz
//#define BAUD  0xFA00                  // 2400bps @ 11.0592MHz
//#define BAUD  0xFD00                  // 4800bps @ 11.0592MHz
//#define BAUD  0xFE80                  // 9600bps @ 11.0592MHz
//#define BAUD  0xFF40                  //19200bps @ 11.0592MHz
//#define BAUD  0xFFA0                    //38400bps @ 11.0592MHz


sfr AUXR = 0x8E;
sbit RXB = P3^0;
sbit TXB = P3^1;

typedef bit BOOL;
typedef unsigned char BYTE;
typedef unsigned int WORD;

BYTE TBUF,RBUF;
BYTE TDAT,RDAT;
BYTE TCNT,RCNT;
BYTE TBIT,RBIT;
BOOL TING,RING;
BOOL TEND,REND;

void UART_INIT();

BYTE t, r;
BYTE buf[16];

//-----------------------------------------
//Timer interrupt routine for UART

void tm0() interrupt 1
{
    if (RING)
    {
        if (--RCNT == 0)
        {
            RCNT = 3;                   //reset send baudrate counter
            if (--RBIT == 0)
            {
                RBUF = RDAT;            //save the data to RBUF
                RING = 0;               //stop receive
                REND = 1;               //set receive completed flag
            }
            else
            {
                RDAT >>= 1;
                if (RXB)
                    RDAT |= 0x80;  //shift RX data to RX buffer
            }
        }
    }
    else if (!RXB)
    {
        RING = 1;                       //set start receive flag
        RCNT = 4;                       //initial receive baudrate counter
        RBIT = 9;                       //initial receive bit number (8 data bits + 1 stop bit)
    }

    if (--TCNT == 0)
    {
        TCNT = 3;                       //reset send baudrate counter
        if (TING)                       //judge whether sending
        {
            if (TBIT == 0)
            {
                TXB = 0;                //send start bit
                TDAT = TBUF;            //load data from TBUF to TDAT
                TBIT = 9;               //initial send bit number (8 data bits + 1 stop bit)
            }
            else
            {
                TDAT >>= 1;             //shift data to CY
                if (--TBIT == 0)
                {
                    TXB = 1;
                    TING = 0;           //stop send
                    TEND = 1;           //set send completed flag
                }
                else
                {
                    TXB = CY;           //write CY to TX port
                }
            }
        }
    }
}

void UART_INIT()
{
    TMOD = 0x00;                        //timer0 in 16-bit auto reload mode
    AUXR = 0x80;                        //timer0 working at 1T mode
    TL0 = BAUD;
    TH0 = BAUD>>8;                      //initial timer0 and set reload value
    TR0 = 1;                            //tiemr0 start running
    ET0 = 1;                            //enable timer0 interrupt
    PT0 = 1;                            //improve timer0 interrupt priority
    EA = 1;                             //open global interrupt switch

    TING = 0;
    RING = 0;
    TEND = 1;
    REND = 0;
    TCNT = 0;
    RCNT = 0;
}

void SendByte(char aByte)
{
    while(!TEND);
    TEND = 0;
    TBUF = aByte;
    TING = 1;
}
char RecvByte()
{
    while(!REND);
    REND = 0;
    return RBUF;
}

void SendData(char* pData, int len)
{
    int i;
    for(i=0; i<len; i++)
    {
        SendByte(pData[i]);
    }
}


void SendHEX(unsigned char Data)
{
    unsigned char highByte = (Data >> 4);
    unsigned char lowByte = (Data & 0X0F);

    highByte += 0x30;
    if (highByte > 0x39)
    {
             SendByte(highByte + 0x07);
    }
    else
    {
             SendByte(highByte);
    }

    lowByte += 0x30;
    if (lowByte > 0x39)
    {
        SendByte(lowByte + 0x07);
    }
    else
    {
         SendByte(lowByte);
    }
}



void SendLR()
{
    SendByte('\r');
    SendByte('\n');
}

void SendStr(char* pData)
{
    int i = 0;;
    while(pData[i] != '\0')
    {
        SendByte(pData[i++]);
    }
}



/*----------------------------
软件延时
----------------------------*/
void Delay(BYTE n)
{
    WORD x;

    while (n--)
    {
        x = 0;
        while (++x);
    }
}



#define IAP_ADDRESS_1 0x0000   // 扇区1 起始地址  共512 Byte
#define IAP_ADDRESS_2 0x0200   // 扇区2 起始地址  共512 Byte


void main()
{
    unsigned int aByte;
    UART_INIT();

    while (1)
    {                                   //user's function
        eeprom_erase(IAP_ADDRESS_1);
        Delay(15);
        eeprom_erase(IAP_ADDRESS_2);
        Delay(15);

        //////////////////////////////////////////////////
        SendStr("sector_1 after eeprom_erase");
        SendLR();
        for(aByte = 0; aByte < 512; aByte++) // [0 ~ 511]
        {
            SendHEX(eeprom_read(IAP_ADDRESS_1 + aByte));
            SendStr(" ");
        }
        SendLR();

        SendStr("sector_2 after eeprom_erase");
        SendLR();
        for(aByte = 0; aByte < 512; aByte++) // [0 ~ 511]
        {
            SendHEX(eeprom_read(IAP_ADDRESS_2 + aByte));
            SendStr(" ");
        }
        SendLR();

        //////////////////////////////////////////////////
        SendStr("sector_1 Write  Read");
        SendLR();
        for(aByte = 0; aByte < 512; aByte++) // [0 ~ 511]
        {
            eeprom_write(IAP_ADDRESS_1 + aByte, (aByte % 256));
        }

        for(aByte = 0; aByte < 512; aByte++) // [0 ~ 511]
        {
            SendHEX(eeprom_read(IAP_ADDRESS_1 + aByte));
            SendStr(" ");
        }
        SendLR();

        SendStr("sector_2 Write Read");
        SendLR();
        for(aByte = 0; aByte < 512; aByte++) // [0 ~ 511]
        {
            eeprom_write(IAP_ADDRESS_2 + aByte, 0xff - (aByte % 256));
        }

        for(aByte = 0; aByte < 512; aByte++) // [0 ~ 511]
        {
            SendHEX(eeprom_read(IAP_ADDRESS_2 + aByte));
            SendStr(" ");
        }
        SendLR();

        Delay(45);

    }
}