Freezing mbed by chaning the system time...

12 Mar 2011

The whole story is: I created a project, coded the program, downloaded the binary code in mbed and run the program on it. And then, I changed the local system time on my computer to several days ago. After that, I added some lines more code into program, compiled and downloaded. I found the several lines of code I just added, had never been excuted on mbed. The reason maybe the time tag on the new file is older than that in the memory of mbed, so the new binary file with older time tag cannot be excute....

Another guess or you can try is, setting your local system time as some time in futre, say year 2020, then compile a program, download into mbed and run it. After you doing this, you cannot use your mbed anymore untill that time in 2020, or you have to always set your local system time on computer as some time after that....

Kind of Frozen mbed, or a nice lock~ lol

12 Mar 2011

remove all the .bin files from your mbed, make a simple program (flash leds) program mbed,

re-compile your program & send to mbed.

That should fix it. as mbed checks for .bin with newest date time stamp.

Enjoy

Ceri

13 Mar 2011

Hi,

Unfortunately, removing all the .bin files from the mbed disk does not solve the problem. There seem to be two checks before the mbed magic chip reprograms a .bin. The .bin should be the newest one on the file system AND it must be newer than the last .bin programmed into the target chip. The result of this is that if your system clock inadvertently shifts, the magic chip refuses to reprogram a newer .bin. The latter check is probably present for efficiency reasons, so that the magic chip does not have to reprogram on every reset.

The more serious problem with this mechanism is that if the system clock ever shifts into the future, you have to use a more future date if you want to ever reprogram the mbed.

Zainul.

13 Mar 2011

Daft question, but I assume you power cycle the MBED between each step, erase MBED disk Power cycle Try adding a new program. Power cycle.

I don't know if it might help, but you could re-flash the magic chip: http://mbed.org/users/no2chem/notebook/mbed-power-controlconsumption/

This might help.

As a very last resort, if you can get access to the ISP pin, then you might be able to use flash magic to program The LPC 1768 itself :c

Cheers Ceri