This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

ReadWrite EEPROM in 89S8252

I got a code, and modified it to run..
But i can't seem to get the code correct.
it has to do with XDATA but i can't seem to get it right.

#include <AT898252.H>
#include "lcd.c"


BYTE ReadEEPROM(int addr)
{
	char EEdata;
	WMCON |= 0x08; // Enable EEPROM memory space

	EEdata = addr; // --> how do u write here?

	WMCON &= 0xF7; // Disable EEPROM memory space
	return(EEdata);
}

// To write a single byte to a location in EEPROM.

void WriteEEPROM(int addr, char EEdata)
{
	WMCON |= 0x08; // Enable EEPROM memory space
	WMCON |= 0x10; // Enable EEPROM memory write

	addr = EEdata; --> how do u write here?

	msdelay(15);
	WMCON &= 0xEF; // Disable EEPROM memory write
	WMCON &= 0xF7; // Disable EEPROM memory space
}

here's the assembly version..it worked..
but didn't manage to convert it into C.


WMCON DATA 96h ; watchdog and memory control register
EEMEN EQU 00001000b ; EEPROM access enable bit
EEMWE EQU 00010000b ; EEPROM write enable bit
WDTRST EQU 00000010b ; EEPROM RDY/BSY bit
ADDRESS EQU 10H
DATAS EQU 0AAH

; EEPROM read example.

;orl WMCON, #EEMEN ; enable EEPROM accesses
;mov dptr, #ADDRESS ; address to read
;movx a, @dptr ; read EEPROM
;xrl WMCON, #EEMEN ; disable EEPROM accesses

; EEPROM write example, utilizing fixed delay for write cycle.
; Delay is worst case (10 ms). Code for delay is not shown.
; Write is followed by verify (read and compare), but code to handle
; verification failure is not shown.


orl WMCON, #EEMEN ; enable EEPROM accesses
orl WMCON, #EEMWE ; enable EEPROM writes

mov dptr, #ADDRESS ; address to write
mov a, #DATAS ; data to write
movx @dptr, a ; write EEPROM

xrl WMCON, #EEMWE ; disable EEPROM writes
xrl WMCON, #EEMEN ; disable EEPROM accesses

Parents

0 Crist Lime over 20 years ago

Ok. I did the adjustments as u suggested..
Seems there is no syntax error..
However I can't seem to build it..
Alot of errors while building it..

Heres the

Eeprom.c

#include <AT898252.H>

#ifndef BYTE
#define BYTE unsigned char
#endif

typedef
    volatile BYTE xdata
    Eeprom;

#define EepromEnable     0x08
#define EepromWriteEn    0x10
#define EepromEnableRead  WMCON |=  EepromEnable
#define EepromEnableWrite WMCON |=  (EepromEnable | EepromWriteEn)
#define EepromDisable     WMCON &= ~(EepromEnable | EepromWriteEn)

BYTE ReadEEPROM(Eeprom* addr);
void WriteEEPROM(Eeprom* addr, BYTE eeData);
void msdelay(unsigned x);

BYTE ReadEEPROM(Eeprom* addr)
{
	BYTE eeData;
    EepromEnableRead;

	eeData = *addr;

 	EepromDisable;
	return eeData;
}

void WriteEEPROM(Eeprom* addr, BYTE eeData)
{
	EepromEnableWrite;

	*addr = eeData;

	msdelay(15);
	EepromDisable;
}

void msdelay(unsigned int x)
{
    BYTE delval;
    while(x--)
    {
        delval = 123; /* Modify thisvalue to tune delay for 1mS */
        while(delval--)
            ;
    }
}

And here's the main test to run it Eeprom.c

test.c


#include <AT898252.H>
#include "eeprom.c"

void main()
{
	Eeprom* addr=0;
	BYTE b=0,eeData=0x3F;

	for(b=0;b<9;b++)
	{
		WriteEEPROM(*(addr+b),eeData);
	}

}

Reply

0 Crist Lime over 20 years ago

Ok. I did the adjustments as u suggested..
Seems there is no syntax error..
However I can't seem to build it..
Alot of errors while building it..

Heres the

Eeprom.c

#include <AT898252.H>

#ifndef BYTE
#define BYTE unsigned char
#endif

typedef
    volatile BYTE xdata
    Eeprom;

#define EepromEnable     0x08
#define EepromWriteEn    0x10
#define EepromEnableRead  WMCON |=  EepromEnable
#define EepromEnableWrite WMCON |=  (EepromEnable | EepromWriteEn)
#define EepromDisable     WMCON &= ~(EepromEnable | EepromWriteEn)

BYTE ReadEEPROM(Eeprom* addr);
void WriteEEPROM(Eeprom* addr, BYTE eeData);
void msdelay(unsigned x);

BYTE ReadEEPROM(Eeprom* addr)
{
	BYTE eeData;
    EepromEnableRead;

	eeData = *addr;

 	EepromDisable;
	return eeData;
}

void WriteEEPROM(Eeprom* addr, BYTE eeData)
{
	EepromEnableWrite;

	*addr = eeData;

	msdelay(15);
	EepromDisable;
}

void msdelay(unsigned int x)
{
    BYTE delval;
    while(x--)
    {
        delval = 123; /* Modify thisvalue to tune delay for 1mS */
        while(delval--)
            ;
    }
}

And here's the main test to run it Eeprom.c

test.c


#include <AT898252.H>
#include "eeprom.c"

void main()
{
	Eeprom* addr=0;
	BYTE b=0,eeData=0x3F;

	for(b=0;b<9;b++)
	{
		WriteEEPROM(*(addr+b),eeData);
	}

}

Children

No data