LPC4330 Xplorer Booting from Reset Problem

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by joohyun.seo on Wed Aug 27 08:27:37 MST 2014

I am experiencing difficulty in in booting from reset. I am using a KEIL debugger, and I have played around with periph_blinky example, but I think I am missing some concept that doesn't only apply to KEIL.

I think I can successfully download the image to both internal flash (using DFUSec) and to external flash. I can see that the 12 MHz crystal is oscillating after I download the image. However, it doesn't start the code or main(). When I press Reset switch on the board, then the boot should be initiated from the internal flash if P2_7 is sampled high. Since I successfully downloaded the image into internal flash P2_7 is high when I RESET, and I expect to start the program from internal flash, but nothing happens. I also reset the board while sampling P2_7 to be low with boot switch configured for external flash, but nothing happens.

I think that the image that I download does not include something like 'startup from reset'. When I run the code for targeting external flash in the Debugger mode, then the code runs fine. I can even make the target address to be internal flash (Device : LPC4337 IROM Address starting from : 0x1A000000, and making setup(0x1A000000) in *.ini file). In both cases, once I run the code in Debugger mode, then it runs fine.

However, I cannot just make the code run by simply pressing the reset switch. I feel that the example code is meant to be debugging purpose so that the code should not be automatically executed, but I hope to implement the code that is executed from the reset.

Please help me learn more about this issue.