topic Re: lpc1768 flash and vector table for an application in LPC Microcontrollers

lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:48 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Tue Sep 16 22:41:41 MST 2014
hello ,
I want to jump to an address ( for example 0xa000)( sector 10 in lpc1768)
I use this code but it it;s not working! what is the reason?
asm("MOV R2 , #0Xa000");

asm("BLX R2");

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:49 GMT

Content originally posted in LPCWare by LabRat on Tue Sep 16 22:51:59 MST 2014
What's in sector 10? An executable code or a vector table?

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:49 GMT

Content originally posted in LPCWare by Pacman on Tue Sep 16 23:43:35 MST 2014
Would the following work ?

asm("movw r2,#0xa001; blx r2");

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:50 GMT

Content originally posted in LPCWare by LabRat on Tue Sep 16 23:56:47 MST 2014

Quote: Pacman
Would the following work ?

asm("movw r2,#0xa001; blx r2");

:quest:

And what's in your 0xa001?

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:50 GMT

Content originally posted in LPCWare by wmues on Wed Sep 17 00:37:24 MST 2014
Bit 0 of your address must be set to 1, because it's a marker of THUMB mode. And the Cortex-M3 is a THUMB arm controller.

But why not make it in C?

void (*mycall) (void) = (void (*)(void)) 0xa001;

mycall();

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:51 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Wed Sep 17 00:43:01 MST 2014
my application program will be statrt at this address.
and I need this code for my bootloader.

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:51 GMT

Content originally posted in LPCWare by LabRat on Wed Sep 17 00:49:14 MST 2014

Quote: dariush_abbasi868
my application program will be statrt at this address.
and I need this code for my bootloader.

Then this sector is including a vector table :exmark:

To start an user application it's necessary to set SP, PC and vector table as described in AN10866:

__asm void boot_jump( uint32_t address ){
   LDR SP, [R0];Load new stack pointer address
   LDR PC, [R0, #4];Load new program counter address
}

void execute_user_code(void)
{
/* Change the Vector Table to the USER_FLASH_START 
in case the user application uses interrupts */
SCB->VTOR = USER_FLASH_START & 0x1FFFFF80;

boot_jump(USER_FLASH_START);
}

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:52 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Wed Sep 17 00:52:11 MST 2014
void (*mycall) (void) = (void (*)(void)) 0x0001;

mycall();
at first I am going to tesst reset (0x00) !!
by above code my program is hanging and goes to cstartup.s file B Default_Handler line!!!
my compiler is IAR.

but by asm("movw r2,#0xa001; blx r2"); it go to the next line and do nothing?!!!!!!!!!

what's wrong?

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:53 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Wed Sep 17 00:57:31 MST 2014

Quote:

Then this sector is including a vector table Exclamation Mark

To start an user application it's necessary to set SP, PC and vector table as described in AN10866:

__asm void boot_jump( uint32_t address ){
LDR SP, [R0];Load new stack pointer address
LDR PC, [R0, #4];Load new program counter address
}

void execute_user_code(void)
{
/* Change the Vector Table to the USER_FLASH_START
in case the user application uses interrupts */
SCB->VTOR = USER_FLASH_START & 0x1FFFFF80;

boot_jump(USER_FLASH_START);
}

I have to call this two function at first an then use jump or not?
if I want ti jump to another sector this two function the same?

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:53 GMT

Content originally posted in LPCWare by LabRat on Wed Sep 17 01:22:29 MST 2014
Please read AN10866 :exmark: :exmark:

AN10866 is describing that the first word in a vector table is the stack pointer and [color=#f00]the second word is the program start address[/color].

So you just have to define the correct start address of your first application code sector in USER_FLASH_START and then call function execute_user_code()...

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:54 GMT

Content originally posted in LPCWare by mc on Wed Sep 17 08:59:00 MST 2014
Hi dariush,
Not sure, if you also want to relocate your vector table. If you just want to jump you can used method mentioned by Wumes.
So if you want to jump at ADDRESS location you can use

void (*mycall) (void) = (void (*)(void)) ADDRESS+1;

mycall();

You will have to put a function at location ADDRESS so that you can test it.

There is another app note which explains it in more detail. It also uses c code to jump.
http://www.lpcware.com/content/nxpfile/an11257-spi-secondary-boot-loader

It may be helpful for you.

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:54 GMT

Content originally posted in LPCWare by LabRat on Wed Sep 17 09:32:49 MST 2014

Quote: mc
Not sure, if you also want to relocate your vector table.

Of course. He's talking about a bootloader

AN11257 is relocating the vector table in user application :exmark:

I don't think that his user application is doing that. Therefore I would strongly recommend to load new SP and vector table in bootloader code as described above....

Of course that's also doable in C:

void execute_user_code(void)
{
 void (*user_code_entry)(void);

 unsigned *p;// used for loading address of reset handler from user flash

 /* Change the Vector Table to the USER_FLASH_START
 in case the user application uses interrupts */

 SCB->VTOR = (USER_START_SECTOR_ADDRESS & 0x1FFFFF80);

 // Load contents of second word of user flash - the reset handler address
 // in the applications vector table
 p = (unsigned *)(USER_START_SECTOR_ADDRESS +4);
 // Set user_code_entry to be the address contained in that second word
 // of user flash
 user_code_entry = (void *) *p;
 // Jump to user application
  user_code_entry();
}

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:55 GMT

Content originally posted in LPCWare by whitecoe on Wed Sep 17 09:38:42 MST 2014
Also - watch the setup of your stack pointer. Lots of previous posts about this if you do a forum search for something like "bootloader stack", for example:

http://www.lpcware.com/content/forum/lpc1768-secondary-usb-bootloader-lock#comment-1133905

HTH!

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:56 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Sat Sep 20 00:39:08 MST 2014
hello
As I am a beginner , at first I want to have a application that start from sector 10 (0xa000) and everything in it is from 0xa000 (vector table and flash) and it can work by itself without secondary boot loader.
is it possible ? I am working with Iar and :

[img=220x150]http://i59.tinypic.com/2d8nu5v.jpg[/img]

[img=50x70]http://http://i62.tinypic.com/2r5u8h0.jpg[/img]

[img=220x150]http://i62.tinypic.com/122292b.jpg[/img]

when i select rom adress at 0xa000 and vector in 00 it's working but at 00 i have something and i want to use this part for my boot loader at future ! when i select vector address at 0xa00 and rom both at a000 it's not working.
what is wrong?

maybe I have to do something in VTOR !!

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:56 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Sat Sep 20 05:41:43 MST 2014
BY default boot vector and ram address are 00 and when I program in 0o address there are something and after that some ff and from 0x300 start my application ( why 0x300? )
and when I change both of them to 0xa000 and SCB->VTOR = 0XA000; at 0xa00 start but I can not find 0x300(!) and data are continual .
and program not working .

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:57 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Mon Sep 22 03:47:34 MST 2014
pls help me

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:57 GMT

Content originally posted in LPCWare by kabikov on Mon Sep 22 04:41:32 MST 2014
Do you write your own bootloader that start your program form 0xA000?
Do you ignore interrupt and turn off preferential that used in bootloader?

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:58 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Mon Sep 22 06:04:18 MST 2014
hello
my own boot loader stat at 00 and in this program i will jump to 0xa000 ( in this part I havenot any problem )
my problem is in my application .
when i use application in 00 address and also it's vectors is is working by itself ( without bootloader)
when I want to use it for application I have to set its start address at 0xa00 and also it's vector address because I have to use 00 address for bootlaoder.
how I can set all of my application program in a000 (rom and vectors ) and when i jump to this address application run .

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:59 GMT

Content originally posted in LPCWare by kabikov on Mon Sep 22 09:24:46 MST 2014
You say jump to 0xA000... But this is stack pointer for your firmware. Do you set new stack pointer from 0xA000? You should jump to address contains in 0xA004. Are you sure that your bootloader upload firmware correctly (CRC)? Are you reserve memory for IAP as described?
May be you post your code?

Re: lpc1768 flash and vector table for an application

lpcware — Wed, 15 Jun 2016 17:21:59 GMT

Content originally posted in LPCWare by dariush_abbasi868 on Mon Sep 22 23:32:53 MST 2014
thank you kabiko !
first and at time point I want to make a application that start from 0xa000( without any bootloader)
i have this application , and it's working in the address 00, in the pictures i attached what i have to do to it start from 0xa000 (every thing in .bin output file such as vectores and rom )
what i have to do for this ?

after that I am going to add this application to my bootloader .
first pls help me to make my application alone.