Posts: 0

Ultra II writing without any file system?


i need some help urgent.


we have buy many SD Card Ultra II with 2 GB.


We design an board with an micro controller that use the sd card like an flash eeprom.

An File system is not necessary. i write the data direct on the sectors (raw)


the first attemps all works great, i can read and write without any problmens.

but at once it is impossible to write on the card. 

i plug the card in the computer and it is impossible to write or format the sd-card.

i write for testing purpose some byte on sector 0, with the program (HxD) under windows, the data was written,

but after an reload (f5) the changes was rejected.

-> the card stops working with the microcontroller and computer


the write cycles was not above 5000.


is the card locked or what happend?


i can read the complete card with HxD, but i cant write under windows

and although the microcontroller cant write anything?



What happend?


Plz help me!



thx for your reply

Posts: 0

Re: Ultra II writing without any file system?

If the card stopped working on a computer reader it means that it has failed to work.