POWER DOWN Memory Corruption
Added by John Mladenik about 14 years ago
Software guys tell me they had a case where the FLASH memory was corrupted when the power was removed at the wrong time. This would be a disaster for us if this happened in the operating room. It sounds like we need to have either a capacitor or Battery to hold up the Power on the MityDSP when power is going low. Have you thoguht about this at all? Do you have any suggestions for dealing with this?
Thanks
John Mladenik
Replies (3)
RE: POWER DOWN Memory Corruption - Added by Thomas Catalino about 14 years ago
John -
We are indeed aware of this and are working on a solution. We plan to allow for the root file system to be mounted as a read-only file system (currently it's mounted read-write). Mounting the root file system read only will allow power to be removed at any time without impacting the integrity of the root file system, and therefore, the system's ability to boot. Once we have this capability we will make it available to all customers.
Having said this, we recognize that customers will want to use the NAND flash to also mount a user file system read-write in order to record data or logging information. As with writing to any flash in an embedded system, care must be taken in the application to deal with a power failure during a write operation.
Tom Catalino
RE: POWER DOWN Memory Corruption - Added by John Mladenik about 14 years ago
So do you think we need to put on our mother board a circuit to hold up the power and interrupt the OMAP to let it know power is going down? Or do you think that your read-only mount will be all that is needed?
thanks for the quick reply and yes I think my FPGA problem is solved.
John
RE: POWER DOWN Memory Corruption - Added by Thomas Catalino about 14 years ago
If your application will not be writing to the NAND flash then you should not need hold-up circuit from the motherboard. However, if you plan to mount a user filesystem rw, and plan to write to it during normal operation, then you may want to consider it, or other means to insure the filesystem will not be corrupt. For example, always having a backup of your data file (and a way to validate it's integrity) may be a reasonable way to deal with this issue. There may be other techniques as well that I'm not immediately aware of.
Tom Catalino
