User Manual
311
Rev. 1.1
2019-03-18
TLE984xQX
Microcontroller with LIN and Power Switches for Automotive Applications
NVM Module (Flash Memory)
BootROM (called Service Algorithm) is automatically started, identifies this tearing case of respective logical
page and repairs the NVM state, ensuring that either the old or the new data (or both) are fully valid.
12.2.9
Dynamic Address Scrambling
Figure 56 Dynamic address scrambling through map-RAM
Starting from the system address space of the NVM, the NVM module supports mapping of pages within each
sector. As described above, this is useful for tearing-safe programming, but it also provides a dynamic address
scrambling: After programming a page the new information is physically stored in a different page in the same
sector. The logical page address and therefore the physical memory address stays the same. For this reason
the mapping is fully transparent for the customer software.
12.2.10 Linearly Mapped Sectors
A number of sectors can be configured not to use the map-RAM mapping mechanism, i.e. for these sectors
logical and physical page addresses are identical. The range of these linearly mapped sectors always starts at
the lowest NVM address of the NVM module, extending upwards to higher addresses. For these sectors
(intended to mainly store executable code without the need for tearing-save programming) no reconstruction
of the map-RAM content after reset is necessary, which saves time during the sleep-wake-up and power-up of
the chip.
For memories with more than 16 sectors (the maximum number of sectors currently supported by the map-
RAM), the remaining lower sectors are always linearly mapped.
12.2.11 Disturb Handling
Due to the implementation of the cell array, while writing a page into the cell array all other pages within the
same sector are slightly written (disturbed) too. If some pages of a sector are changed often and other pages
of the same sector only rarely, these rarely programmed pages may be disturbed too often and loose their
data.
NVM memory
address
space
sector
..
.
sector
..
.
map-RAM
system memory
sector and logical
page address
sector and
physical pages