Table 3. Memory Security And Privilege Access - ST STM32WL55JC Reference Manual

2.6 Memory organization
2.6.1 Introduction
Program memory, data memory, registers and I/O ports are organized within the same linear
4-Gbyte address space.
The bytes are coded in memory in Little Endian format. The lowest numbered byte in a word
is considered the word's least significant byte and the highest numbered byte the most
significant.
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