Greg, Ok, I can boot the SAMA5D3-Xplained board to the NuttX shell using the procedure you outlined! (Loading the nuttx binary into RAM using the J-Link debugger.) Thank you! Super! NSH is accessible via the DBGU port.
I'll try the same procedure on the SAMA5D2-XULT board either tomorrow or in the next few days. Now... to figure out how go get the D3 board to boot from flash or the SD Card. :) I will try to follow the README file. Thank you so much! cheers adam On Sun, Dec 22, 2019 at 9:32 PM Gregory Nutt <spudan...@gmail.com> wrote: > > Make sure you compile with debug info enabled and no optimization. > Then, since you mentioned you have a Segger J-Link JTAG probe, I highly > recommend you use Segger’s debugger Ozone (free J-Link probes) — you’ll be > able to easily single-step and determine what’s going wrong… > > If you have a J-Link then you are in business and it shouldn't be > difficult to find the problem. You can use the J-Link like this: > > * Start U-Boot and break out to the prompt. This will initialize the > SDRAM. > * Then load NuttX in SDRAM and debug it. > > The first think I would want to know is does the code get to nsh_main(). > > * gdb> file nuttx > * gdb > b nsh_main > * gdb> mon reset > * gdb> c > > If you get there, then all of the initialization went OK. Then put a > breakpoint on fputs(). You should hit it via > > nsh_session.c: fputs(g_nshgreeting, pstate->cn_outstream); > > If you get there then it is at least trying to get something on the > serial console, but is failing for some reason: maybe wrong UART or > wrong pin configuration. > > > -- Adam Feuer <a...@starcat.io>
