Difference between revisions of "Mbed IAP flash write"

Latest revision as of 16:51, 11 September 2015

• Tedd OKANO IAP_internal_flash_write

Control where code is written and where to write data with IAP

Keil

• Flash starts at 0x0000
  • Keil R/O base at 0x8000 if not defined
    • Use Memory Layout from Target Dialog is not active (mbed export project)
      • So sectors 0 to 7 are not affected and can be used by IAP
• Erase sector (=4096 bytes for the first 10 sectors)
• May write only 256 bytes in the sector

mbed compiler

• TODO

Find where is the R/O base

code

<cpp> //IAP_internal_flash_write_NX //imported 2012.05.14

/** IAP demo : demo code for internal Flash memory access library

*
*        The internal Flash memory access is described in the LPC1768 usermanual. 
*            http://www.nxp.com/documents/user_manual/UM10360.pdf
*
*            Chapter  2: "LPC17xx Memory map"
*            Chapter 32: "LPC17xx Flash memory interface and programming"
*                refering Rev. 01 - 4 January 2010
*
*  This main.cpp demonstrates how the flash can be erased and wrote.
*
*  This program tries to...
*    0. read device ID and serial#
*    1. check if the targat sector blank
*    2. erase the sector if it was not blank
*    3. write into the flash (prepare before write)
*    4. verify the data by IAP command
*    5. show the content of the flash
*
*  The Flash must be erased as sectors. No overwrite can be done like SRAM. 
*  So erase should be done in size of 4K or 32K. 
*
*  Writing sector can be done with size of 256, 512, 1024 or 4096. 
*  If other size is used, the IAP returns an error. 
*  The SRAM memory should be allocated in 
*
*
*  Released under the MIT License: http://mbed.org/license/mit
*
*        revision 1.0  09-Mar-2010   1st release
*        revision 1.1  12-Mar-2010   chaged: to make possible to reserve flash area for user
*                                            it can be set by USER_FLASH_AREA_START and USER_FLASH_AREA_SIZE in IAP.h
*/

1. include "mbed.h"
2. include "IAP.h"

1. define MEM_SIZE 256
2. define TARGET_SECTOR 29

void memdump( char *p, int n ); int isprint( int c );

IAP iap;

int main() {

   char    mem[ MEM_SIZE ];    //  memory, it should be aligned to word boundary
   int     r;

   printf( "IAP: Flash memory writing test\n" );
   printf( "  device-ID = 0x%08X, serial# = 0x%08X, CPU running %dkHz\n", iap.read_ID(), iap.read_serial(), SystemCoreClock / 1000 );
   printf( "  user reserved flash area: start_address=0x%08X, size=%d bytes\n", iap.reserved_flash_area_start(), iap.reserved_flash_area_size() );

   for ( int i = 0; i < MEM_SIZE; i++ )
       mem[ i ]    = i & 0xFF;

   //  blank check: The mbed will erase all flash contents after downloading new executable

   r   = iap.blank_check( TARGET_SECTOR, TARGET_SECTOR );
   printf( "blank check result = 0x%08X\n", r );

   //  erase sector, if required
   
   if ( r == SECTOR_NOT_BLANK ) {
       iap.prepare( TARGET_SECTOR, TARGET_SECTOR );
       r   = iap.erase( TARGET_SECTOR, TARGET_SECTOR );
       printf( "erase result       = 0x%08X\n", r );
   }
   
   // copy RAM to Flash

   iap.prepare( TARGET_SECTOR, TARGET_SECTOR );
   r   = iap.write( mem, sector_start_adress[ TARGET_SECTOR ], MEM_SIZE );
   printf( "copied: SRAM(0x%08X)->Flash(0x%08X) for %d bytes. (result=0x%08X)\n", mem, sector_start_adress[ TARGET_SECTOR ], MEM_SIZE, r );

   // compare

   r   = iap.compare( mem, sector_start_adress[ TARGET_SECTOR ], MEM_SIZE );
   printf( "compare result     = \"%s\"\n", r ? "FAILED" : "OK" );

//#define WRITE_NEXT_BLOCK

1. ifdef WRITE_NEXT_BLOCK

   // copy RAM to Flash

   iap.prepare( TARGET_SECTOR, TARGET_SECTOR );
   r   = iap.write( mem, sector_start_adress[ TARGET_SECTOR ] + 256, MEM_SIZE );
   printf( "copied: SRAM(0x%08X)->Flash(0x%08X) for %d bytes. (result=0x%08X)\n", mem, sector_start_adress[ TARGET_SECTOR ], MEM_SIZE, r );

   // compare

   r   = iap.compare( mem, sector_start_adress[ TARGET_SECTOR ] + 256, MEM_SIZE );
   printf( "compare result     = \"%s\"\n", r ? "FAILED" : "OK" );

1. endif

   printf( "showing the flash contents...\n" );
   memdump( sector_start_adress[ TARGET_SECTOR ], MEM_SIZE * 3 );

}

void memdump( char *base, int n ) {

   unsigned int    *p;

   printf( "  memdump from 0x%08X for %d bytes", (unsigned long)base, n );

   p   = (unsigned int *)((unsigned int)base & ~(unsigned int)0x3);

   for ( int i = 0; i < (n >> 2); i++, p++ ) {
       if ( !(i % 4) )
           printf( "\n  0x%08X :", (unsigned int)p );

       printf( " 0x%08X", *p );
   }

   printf( "\n" );

}

</cpp>