Erase In Flash Program

[ponsakthi]

can i erase a word in pic18f flash program memory?

if yes... please tell me how

 

[Pommie]

You have to erase a full block each time. The only way to erase a word is to read the block into ram, erase it and write back the block with the word erased.

Mike.

 

[3v0]

What pommie said

 

[ponsakthi]

thanks pommie

do u have any c program to read write data into program memory block. am working in pic18f (mplab)

 

[ponsakthi]

asssembly equivalent

what is the equivalent in C for the following assembly mnemonics



tblwt*+;

 

[Mike - K8LH]

I'd love to know if there's a better way than how I did it in C18;

/*****************************************************************
 *  functions                                                    *
 *****************************************************************/

void TBLWRPOSTINC_Func (void)
{ _asm TBLWTPOSTINC _endasm }

void TBLRDPOSTDEC_Func (void)
{ _asm TBLRDPOSTDEC _endasm }

void TBLRDPOSTINC_Func (void)
{ _asm TBLRDPOSTINC _endasm }

void TBLWR_Func (void)
{ _asm TBLWT _endasm }

/*****************************************************************
 *  erase, write, and verify buffer (64 code or 8 IDLOC bytes)   *
 *****************************************************************/

void Write_Buffer (void)
{ if (Row_Count)                //  don't write an empty buffer
  { Set_TBLPTR ();              //  erase 64 byte 'row'
    Write (0b10010100);         //  EEPGD=1/CFGS=0/FREE=1/WREN=1

    for (x=0; x<Row_Count; x++) //  write 64 byte 'row'
    { TABLAT = Row_Buffer[x];
      TBLWRPOSTINC_Func ();     //
    }
    TBLRDPOSTDEC_Func ();       //  fix TBLPTR, do "long write"
    Write (0b10000100);         //  EEPGD=1/CFGS=0/FREE=0/WREN=1

    Set_TBLPTR ();              //  verify 64 byte 'row'
    for (x=0; x<Row_Count; x++)
    { TBLRDPOSTINC_Func ();
      if (TABLAT != Row_Buffer[x])
      { Error_Flag = 0x04;      //  indicate verify error
      }
      Row_Buffer[x] = 0xFF;     //  reset row buffer byte to FF
    }
    Row_Count = 0;              //  indicate row buffer empty
  }
}

 

[ponsakthi]

flash read write

i am using pic18f series in mplab ide2.
firstly i worked in mplab sim. there i was able to write to program memory and then again read it back.

when i connected the actually hardware using pickit. the flash data is not getting stored in the address which i specify . also out of 60 bytes of data i was ablle to read 50 bytes but not the rest 10 bytes ... please help me in this issue...