HI there,
I´m writing a Flashdriver to be able to write data to the flash memory from a bootloader application. I read a lot about that and searched though the forum but unfortunately didn´t gest the desired results. So my question is, if I can read / write to the complete flash memory by using the LAP register ? The documentation says yes, but it seems to be inconsitent sometimes.
What about the PPAGE method ? Are there pro´s and con´s between both methods ? Anyway, I placed my code below, so maybe anyone can help me. Thank you very much in advance for helping !
void RAM_Routine( tUI16 Address, tUI8 Value, tUI8 Command )
{
/* clear FACCERR flag */
FSTAT |= FSTAT_FACCERR_MASK_UI8;
#ifdef MMU_USAGE == LAP_ADDRESSING
/* set LAP ( Linear Address Pointer ) to desired location */
LAP0 = 0xFF & Address;
LAP1 = 0XFF & ( Address << 8 );
LAP2 = 0xFF & ( Address << 16 );
/*
_asm("PSHA");
_asm("LDA @Address:LINEAR_HIGH");
_asm("STA LAP2");
_asm("LDA @Address:LINEAR_MID");
_asm("STA LAP1");
_asm("LDA @Address:LINEAR_LOW");
_asm("STA LAP0");
_asm("PULA");
*/
/* increment LAP register value / step to next byte in the flash */
LB = Value;
#elif MMU_USAGE == PAGED
/* TODO incrementing of data pointer */
/* step to next byte in the flash */
#else
/* write data to the block to erase */
*(tUI8*)Address = Value;
#endif /*MMU_USAGE*/
/* load command */
FCMD |= Command;
/* set FCBEF to start the command */
FSTAT |= FSTAT_FCBEF_MASK_UI8;
/* wait for four cycles before checking FSTAT register */
(void)FCDIV;
/*was the operation succesful?*/
if( !( FSTAT & FSTAT_ERROR_MASK_UI8 ) )
{
/*wait for FCCF flag*/
while( !( FSTAT & FSTAT_FCCF_MASK_UI8 ) )
{
/*change this to the system used function to reset the watchdog*/
SERVICE_WATCHDOG();
}
}
return;
}
/*** end of RAM_Routine() ***/
