ST STM32WL55JC Reference Manual page 76

RM0453
Example
The following example shows how to map bit [2] of the byte located at SRAM1 address
0x2000 0300 to the alias region. The formula is then:
0x2200 6008 = 0x2200 0000 + 0x0300 * 32 + 2 * 4
Writing to address 0x2200 6008 has the same effect as a read-modify-write operation on bit
[2] of the byte at SRAM1 address 0x2000 0300.
Reading address 0x2200 6008 returns the value 0x01 or 0x00 of bit [2] of the byte at
SRAM1 address 0x2000 0300.
For more information on bit-band, refer to the Cortex-M4 programming manual.
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