3.7.1. Directly accessing an alias region

Writing to a word in the alias region has the same effect as a read-modify-write operation on the targeted bit in the bit-band region.

Bit [0] of the value written to a word in the alias region determines the value written to the targeted bit in the bit-band region. Writing a value with bit [0] set writes a 1 to the bit-band bit, and writing a value with bit [0] cleared writes a 0 to the bit-band bit.

Bits [31:1] of the alias word have no effect on the bit-band bit. Writing 0x01 has the same effect as writing 0xFF. Writing 0x00 has the same effect as writing 0x0E.

Reading a word in the alias region returns either 0x01 or 0x00. A value of 0x01 indicates that the targeted bit in the bit-band region is set. A value of 0x00 indicates that the targeted bit is clear. Bits [31:1] are zero.

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