Re: [lwip-users] Device crashes while connected via TCP and Serial simultaneously

[Sergio R. Caprile]

OK...
you are using some vendor port for some device.
You have to check on your vendor's forums for the intricacies of 
debugging your particular device. I could help with some ARMs and there 
surely are some other guys knowing other processors here, but this is 
not the right place for that.

First things first. Please check your vendor has been a good guy and did 
things properly. If you run with no OS, you must have NO_SYS=1, a main 
loop, and some interrupt handlers. You must call lwIP functions in only 
one context, either main or interrupt, but not both. (you said 1.4.1)
I can't help with SYS_LIGHTWEIGHT_PROT

Then, it would be helpful to know why your device is "crashing". You are 
seeing a data fetch exception, try to get exactly why is that and who is 
fetching where. Do you have some MPU in there ?

> I use another serial interface to send some debug information to my
> developing PC (in synchronous mode)

I don't get what you use, neither if it is relevant for this

>  I have another connection to another part of the GUI

What GUI ? Please properly describe your scenario.
You must start working with small and manageable pieces, if you don't 
know if your port is OK, you need to run applications you know they 
work. Your driver might be trashing memory, your port might be reentring 
non-reentrable functions, your serial handler might be trashing memory, 
your app copying from serial to tcp buffer might be trashing memory. 
What API are you using ? What functions do you use in your app ? Any 
wandering pointer can trigger a data fetch exception. Reduce that to the 
minimum for a test, see if it triggers the exception, track it down, 
post your code here and/or the TI forum respectively.