Run code from power on Link2 dev board

[QM]

Hi NXP community, 

I have two link2 boards working as a debug/target configuration. When I load code onto my target board and debug it, it works fine. However, when I unplug the power and plug it back in again the code doesn't run properly. 

How do I go about figuring out when my issue is? I have tested example code such as the led blinky one, which works as expected (starts blinking at power on). I do notice the example code stores in flash, and needs to be booted with JP1 connected to work, whereas my code doesn't seem to be storing in flash. 

Is the best solution to store my code in flash like the example? or is there a simpler way of telling the program where to start in my code after power on?

Thanks in advance, 

Quinn

[QM]

Hi NXP, 

I still don't have a solution to my problem but I am getting closer to solving it. Like I mentioned in a previous post I believe I have successfully configured my linkscripts to download my code from my flash to my RAM when I power on my board. 

However, I can see with my debugger that the code is still executing from flash and not from RAM as the main starts from an address around 0x14000000, which is the start of my flash memory.

What should I change next to get my code to start from the main that it downloads to RAM and not from the main in flash?

Regards,

Quinn 

[xiangjun_rong]

HI,

On your target board, pls check the JP1 jumper on the LPC link2 board, I suppose you have to close the JP1.

Pls have try.

Hope it can help you

BR

XiangJun Rong

[QM]

Hi XiangJun,

I have tried with JP1 connected but I don’t think I am storing my code to flash so doing this doesn’t change anything.

Quinn

[xiangjun_rong]

Hi,

Pls check if you download application code to on-chip SRAM or external quad SPIFI flash on the target board by checking the link file.

BR

XiangJun Rong

[QM]

Hi XiangJun, 

It looks like I am loading code into SRAM. Please see the images attached of my linker file and MCU settings menu in properties > C/C++ Build > MCU Settings (in MCUExpresso).

Regards, 

Quinn

[xiangjun_rong]

Hi,

I have checked the link file, the application code is put in on-chip RAM, if you want to run the code after power off and on, you have to put the code in external SPIFI flash.

Hope it can hjelp you

BR

XiangJun rong

[QM]

Hi XiangJun, 

I am running from RAM because it I believe it allows me to execute code faster than if the code was stored in external flash. 

I have read on some other forum posts that I could place a dummy main() into flash which then calls the real main() in RAM. Would this be a viable solution which does not affect the performance of the code in RAM? Would you be able to assist me in configuring my program in MCUXpresso to make this happen? 

I do eventually want to design a system which only uses the LPC4370 without external flash. I find it hard to believe that the only way to program this chip and have it run after reset properly is with the code in an external flash, but I could be wrong.

-Quinn

[xiangjun_rong]

Hi,

Yes, the external spifi flash is required, the application code must be saved in flash so that the code can remain after power off.

Hope it can help you

BR

XiangJun Rong

[QM]

Ok yes, I see what you are saying. Is it possible to download and run code from flash to RAM on power on? 

- Quinn

[xiangjun_rong]

Hi,

Yes, it is okay to download and run code from flash to RAM on power on.

BR

XiangJun Rong

[QM]

Hi XiangJun Rong,

Can I get some more help with my issue?

I have read the MCUXpresso guide and followed the steps in 17.15.1 "Relocating majority of an application to RAM." I now have a folder in the project called link scripts with the necessary files mentioned in that section of the guide. 

My code is now running from flash, which is a good step I think as I know now that I am able to save it to the flash. Now it seems like its still not running the code from RAM like I want. It could be copying it to RAM but still running from flash, not entirely sure.

Any suggestions on what to try next?

Regards, 

Quinn

[QM]

Ok so how do I do this?

I have copied the flash configuration used in the Blinky example project for the link2 into my project. It seems to be loading some of the code into the flash but my program still doesn't run as expected.

Please see attached are three images of the storage used after building my program. One with no flash configured, one with flash configured, and an image of the MCU settings for the storage and flash configuration. The one with flash seems to have copied half of my code into flash, but I haven't specified anywhere what should be copied to where. 

Can you suggest some things I need to consider moving forward, or some guide I could follow for getting my code to download to flash during debug and run from RAM?

Thanks, 

Quinn