0x23FF.FFE4
0x2200.0004
0x23FF.FFE0
0x23FF.FFE8
0x23FF.FFEC
0x23FF.FFF0
0x23FF.FFF4
0x23FF.FFF8
0x23FF.FFFC
0x2200.0000
0x2200.0014
0x2200.0018
0x2200.001C
0x2200.0008
0x2200.0010
0x2200.000C
32-MB Alias Region
0
7
0
0
7
0x2000.0000
0x2000.0001
0x2000.0002
0x2000.0003
6
5
4
3
2
1
0
7
6
5
4
3
2
1
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0x200F.FFFC
0x200F.FFFD
0x200F.FFFE
0x200F.FFFF
1-MB SRAM Bit-Band Region
Memory Model
64
SLAU356I – March 2015 – Revised June 2019
Copyright © 2015–2019, Texas Instruments Incorporated
Cortex-M4F Processor
Figure 1-3. Bit-Band Mapping
1.4.5.1
Directly Accessing an Alias Region
Writing to a word in the alias region updates a single 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
clear 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.
When reading a word in the alias region, 0x0000_0000 indicates that the targeted bit in the bit-band region
is clear and 0x0000_0001 indicates that the targeted bit in the bit-band region is set.
1.4.5.2
Directly Accessing a Bit-Band Region
describes the behavior of direct byte, halfword, or word accesses to the bit-band regions.
1.4.6 Data Storage
The processor views memory as a linear collection of bytes numbered in ascending order from zero. For
example, bytes 0-3 hold the first stored word, and bytes 4-7 hold the second stored word. Data is stored in
little-endian format, with the least-significant byte (LSByte) of a word stored at the lowest-numbered byte,
and the most-significant byte (MSByte) stored at the highest-numbered byte.
shows how data
is stored.