Problem with LPC1768 USB bootloader

Without a real fix one thing that worked for me is switching from optimization level 0 to level 1.

I am not sure if I understand the mentioned problem, but if [switching from optimization level 0 to level 1] solves the mentioned problem; then maybe you can increase the size of STACK and HEAP, to see if this increasing solves the mentioned problem.

Without a real fix one thing that worked for me is switching from optimization level 0 to level 1.

I am not sure if I understand the mentioned problem, but if [switching from optimization level 0 to level 1] solves the mentioned problem; then maybe you can increase the size of STACK and HEAP, to see if this increasing solves the mentioned problem.

Hi All,

in the example from NXP is an error. SP register must be set correctly before jump to the user application. I have changed execute_user_code() function:

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

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

        volatile const DWORD *stack_adr = 0x00002000;
        volatile const DWORD *start_adr = 0x00002004;

        __MSR_MSP(*stack_adr);

        NVIC_SetVectorTable(NVIC_VectTab_FLASH, USER_FLASH_START);

        user_code_entry = (void (*)(void))(*start_adr);
        user_code_entry();

}

Regards

Increasing the stack size helped if I commented out one of my ISRs but no matter how much I increase the stack it's not enough for this one.

In the LPC2368 I had to setup stack sizes for all of the ARM modes like IRQ, System, Supervisor, etc. Without doing it I had a similar problem. Do these modes still exist in the 1768? I couldn't find any documentation on it for the 1768 but then again I can barely find any reference of it for the 2368 either. All I could dig up is this one forum post:
www.embeddedrelated.com/.../23503.php

In the LPC1768 (Cortex-M3) there are only two modes:
- Thread mode - TM
- Handler mode – HM.
In addition, there are two levels with different rights of access to key areas in the address space:
- Privileged Level – PL
- Unprivileged/User Level – UL.

That was a huge help thanks! All I had to do was add

mov R0, #0x00
msr CONTROL, R0

into my bootloader startup and everything works! I needed my code to be in Priveleged mode. I was looking for the modes in the NXP User's Manual instead of in the Cortex M3 core manual.

Hi all,

I have the same problem with NXP Ethernet bootloader.

The bootloader works fine with a small program but with bigger program, the user application doesn't start at all. It seems to be stuck at the same address in start_up (command STR Rd, [Rn, Offset]).

The same application works fine, if I compile it to start at address 0x00.

Vector table has been changed to the a new address and it works fine with the smaller application.

I have tried to switch optimization level, it doesn't help at all.
I have tried to set SP register before jumping to the user application. No help.
Both applications are in privileged mode.

Please help me out...

Thanks in advance
Piritta