Firmware User Manual (AE-step)
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Revision 1.02
2019-04-24
TLE984x Firmware User Manual
NVM
written) is triggered. The actions performed by copying a used page inside the data flash sector are the same
as for writing a used data flash page.
5.3
Data Flash Initialization
After a reset the volatile memory, MapRAM, has to be recovered in order to be able to perform the address
translation for data flash accesses. The content of the MapRAM is being recovered out of the MapBlock, control
information stored along with each data flash page. If during the initialization of the MapRAM an error
occurred, i.e. a MapBlock of a data flash page contains ECC failures or if two pages are pointing to the same
MapRAM entry (double mapping) then a repair function is called, the Service Algorithm (SA).
The Service Algorithm (SA) is executed only during startup, by the MapRAM initialization function and only if
failures occurred during the MapRAM initialization. The Service Algorithm scans the entire data flash sector
and tries to repair as much as possible faulty pages, pages with ECC failures in the MapBlock. The SA further
scans for double mappings, pages which point to the same MapRAM entry. Up to one double mapping can be
resolved by deleting one of the two pages. If more than one double mapping is existent the SA is not able to
repair.
The result of the Service Algorithm is being reflected in the register MEMSTAT. The user shall read this register
upon user code entry and in case unrecoverable failures in the data flash are signaled appropriate data flash
recovery has to be performed by the user, such as erase of the entire data flash sector. It is not recommended
to perform any write/erase action to the data flash if the mapping integrity is not given, the status of the
mapping integrity is stored inside MEMSTAT and shall be evaluated by the user upon user code entry.