August 12, 2013

mbed board with new ethernet interface (KEIL debugging problem)

I received an mbed application board the last week! Thank you mbed !

I am very pleased with it & mbed. New hardware platform on my desk and it provides all interfaces I need in the following weeks (perhaps even months). One of the first applications running there was new ethernet interface. As you have noticed, I am inclined to debug the code (oh yes, no TDD yet), if any problem arises. Eventually I run into one, exported an application to KEIL. As soon as it hits eth.init() function, it gets trapped on very famous BKPT instruction. A bit digging into the source code, I found out it was because of a semihosting request of the mac address. It is known issue.

As proposed by mbed guys, it could be easily fixed. I am testing at the moment the implementation of defining own mac address which enables to debug any ethernet code with CMSIS-DAP on mbed board.

One question, has anybody notice the size of ethernet applications (rtos, tcp/ip stack + small application) ?? It's around 87kB of the text size..