Tool/software: TI C/C++ Compiler
In recent time I found a strange problem about memory access. Please refer to the following description for deailed information.
First I assign one-word length zone for a flag which indicate whether need to update the F28022 flash, just like this :
FLASHFLAG : origin = 0x3F6FFF, length = 0x000001
And the original value of the odd address (0x3F6FFF) is 0x55BB , which indicate that it is no need to update the flash and the program run into the normal opearation mode.
What's more, the value of FLASHFLAG could be changed by the external devices, like Tester etc.
Nornally the value is changed to 0x55AA when it is need to update the flash, and the program wait in Boot mode.
However, due to some unknown reasons, the FLASHFLAG was changed to 0x55AA without the external Tester. Certainly something happened, but it's difficult to pinpoint it.
Now I have two questions:
First, is it unreasonable to define a flag to odd address in the flash sector just like "FLASHFLAG : origin = 0x3F6FFF, length = 0x000001"?
Second, what happened when the flash values were changed determinately from 0x55BB to 0x55AA ?
It is appreciated for your sincere reply!