pstorage reading other values than writing

Question

Hi! 
 Maybe I'm doing something wrong (very possible), but for example, when I want to store array of 3 uint8_t values I use: 
 uint8_t dataToStore[3];
dataToStore[0] = 11;
dataToStore[1] = 22;
dataToStore[2] = 33;

retval = pstorage_store(&block_handle, dataToStore, 3 , 0);
	if (retval == NRF_SUCCESS)
	{
 // Store successfully requested. Wait for operation result.
	}
	else
	{
 // Failed to request store, take corrective action.
	}
 
 and when I want to read it from the memory to variable I use: 
 retval = pstorage_block_identifier_get(&persistant_memory_handle, 0, &block_handle);
	if (retval == NRF_SUCCESS)
	{
 uint8_t dest_data[3];
 //Request to read 3 bytes from block at an offset of 0 bytes.
 retval = pstorage_load(dest_data, &block_handle, 3, 0);
 if (retval == NRF_SUCCESS)
 {
 // here dest_data should be: 11, 22, 33 but it gets different values.
 }
 else
 {
 // Failed to load, take corrective action.
 }
 
 Received value is always different than stored. What can be the reason?

Nikita · Accepted Answer

Change 
 uint8_t dataToStore[3];
 
 to 
 static uint8_t dataToStore[4] __attribute__((aligned(4)));
 
 Static because: 
 
 pstorage_store 
 No copy of the data is
made, and hence memory provided for
data source to be written to flash
cannot be freed or reused by the
application until this procedure is
complete. End of this procedure is
notified to the application using the
notification callback registered by
the application. 
 
 And your buffer should be word aligned in ram.

pstorage reading other values than writing

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