External Flash programming algorithm

Hello,

I'm using Keil_4 with ULINK2 to program the LPC1788 of my EA LPC1788 OEM Board.
On this board there's an external NAND Flash (8 bits bus)
I want to program both my application and the external flash data at once.
I modify FlashDev.c end FlashPrg.c but it did not seem to work.

So I started again from scratch.
I copied the _Template directory, let all functions empties (they return OK)
I modified

struct FlashDevice const FlashDevice  =  {
   FLASH_DRV_VERS,             // Driver Version, do not modify!
   "XFlash",   // Device Name
   EXT8BIT,                     // Device Type
   0x90000000,                 // Device Start Address
   0x00040000,                 // Device Size in Bytes (256kB)
   1024,                       // Programming Page Size
   0,                          // Reserved, must be 0
   0xFF,                       // Initial Content of Erased Memory
   100,                        // Program Page Timeout 100 mSec
   3000,                       // Erase Sector Timeout 3000 mSec

// Specify Size and Address of Sectors
   0x010000, 0x000000,         // Sector Size 64kB (2 Sectors)
   SECTOR_END
};

and I then created XFLASH.FLM

On the test program I only have

/* in RO section */
const int acBitmap[20000] __attribute__ ((section ("XFLASH"))) = {
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, ...
};

with the following scatter file

; *************************************************************
; *** Scatter-Loading Description File generated by uVision ***
; *************************************************************

LR_IROM1 0x90000000 0x90800000  {    ; load region size_region
  ER_IROM1 0x90000000 0x90800000  {  ; load address = execution address
   * (XFLASH)
  }
}

On the Debug/Settings/Debug tab my JTAG probe is detected.
On the Utilities/Settings/Flash Download tab I choose my XFlash algorithm.

I then press LOAD !

I got a message "Too Many JTAG Devices in Chain"

What is wrong in my test ?

Thanks for your comment...