[SOLVED] How can i use EEPROM in AT89S8253 micro-controller.

[Varkha Agrawal]

I want to change the preset variable in run time by use of eeprom, please help with coding.

 

[#MAAM#]

I want to change the preset variable in run time by use of eeprom, please help with coding.

what is your compiler ?

 

[Varkha Agrawal]

I am using C compiler and Kiel IDE.

 

[bigdogguru]

The following Atmel Appnote provides an example of an EEPROM write routine in Assembly:

Atmel AT89S8253 Primer

You should be able to port the above Assembly examples to C.


Example C Routines:

void WriteEEPROM (unsigned char xdata *addr, unsigned short Data)
        { // WriteEEPROM

              EECON |= EEMEN;
              EECON |= EEMWE;

              EECON |= EELD;
              *addr = Data >> 8;

              EECON &= ~EELD;
              *(addr+1) = (unsigned char)Data;
              while (!(EECON & EERDY));

              EECON &= ~EEMWE;
              EECON &= ~EEMEN;

        } // WriteEEPROM



 short ReadEEPROM (unsigned char xdata *addr)
        { // ReadEEPROM
            short Result;

             EECON |= EEMEN;
             Result = (*addr << 8) + (*(addr+1));
             EECON &= ~EEMEN;
          
             return (Result);
        } // ReadEEPROM

BigDog

 

[Varkha Agrawal]

Actually problem is that, I want to change my preset value which is store in variable 'a' and display in lcd, suppose i set the value of a=65, but after increment it is saved in EEPROM. when power is off now it should display new value rather than 65. so how can i program for this....................and how can i store the change of value from preset value in same variable.