topic Re: LPC8N04 reset not working in NFC

LPC8N04 reset not working

TheOrangeTeaFrog — Fri, 23 May 2025 09:34:38 GMT

I have the OM40002 dev board. I have downloaded the SDK using the SDK builder (arm-gcc). I build the led_blink example with cmake + make. I flash it to my board with `pyocd flash blink.elf --target lpc8n04`. I see the LED blinking as expected. However, when I press the reset button on the dev board, the LED goes out and never comes back on. This is consistent for other examples and my own program; it works fine when first loaded but doesn't run on reset.

I have also tried using the debugger (gdbserver). I get the same behaviour here: using the `load` command will have the program execute as normal while triggering a reset with pyocd's `reset hardware` command seems to leave me in a weird part of memory (PC is 0x7f3a which seems to be outside of the .text section or any of the other sections visible in `readelf -S` but still inside of the m_text memory area defined in LPC8N04_flash.ld ).

Re: LPC8N04 reset not working

Fabian_R — Fri, 23 May 2025 17:28:08 GMT

Hello, Thank you for your interest in our products.

I am very sorry but we aren't familiarized with pyocd. Unfortunately, NXP can only provide support for our own tools.

As recommended in the product support page, the recommended tool for this is MCUXpresso. We do have a step-by-step guide for start using LPC8N04.

My apologies for the inconveniences this may cause.

Re: LPC8N04 reset not working

TheOrangeTeaFrog — Wed, 28 May 2025 08:22:17 GMT

For anyone with the same issue, I was able to fix this by downloading the IDE, building the blinky example in that and then pulling out the startup code + linker script from the resulting build. The startup code + linker script in the sdk is completely different to these for some reason.