GD32F20x User Manual
38
Pre-defined
Regions
Bus
Address
Peripherals
SRAM
AHB
0x2007 0000 - 0x3FFF FFFF
Reserved
0x2006 0000 - 0x2006 FFFF
Reserved
0x2002 0000 -0x2005 FFFF
SRAM2
0x2001 C000 -0x2001 FFFF
SRAM1
0x2000 0000 - 0x2001 BFFF
SRAM0
Code
AHB
0x1FFF F810 - 0x1FFF FFFF
Reserved
0x1FFF F800 - 0x1FFF F80F
Option Bytes
0x1FFF F000 - 0x1FFF F7FF
Boot loader
0x1FFF E000 - 0x1FFF EFFF
0x1FFF B000 - 0x1FFF DFFF
0x1FFF 7A10 - 0x1FFF AFFF
Reserved
0x1FFF 7800 - 0x1FFF 7A0F
Reserved
0x1FFF 0000 - 0x1FFF 77FF
Reserved
0x1FFE C010 - 0x1FFE FFFF
Reserved
0x1FFE C000 - 0x1FFE C00F
Reserved
0x1001 0000 - 0x1FFE BFFF
Reserved
0x1000 0000 - 0x1000 FFFF
Reserved
0x083C 0000 - 0x0FFF FFFF
Reserved
0x0830 0000 - 0x083B FFFF
Reserved
0x0800 0000 - 0x082F FFFF
Main Flash
0x0030 0000 - 0x07FF FFFF
Aliased to Main
Flash or Boot loader
0x0010 0000 - 0x002F FFFF
0x0002 0000 - 0x000F FFFF
0x0000 0000 - 0x0001 FFFF
1.3.1.
Bit-banding
In order to reduce the time of read-modify-
write operations, the Cortex™-M3 processor
provides a bit-banding function to perform a single atomic bit operation. The memory map
includes two bit-band regions. These occupy the SRAM and Peripherals respectively. These
bit-band regions map each word in an alias region of memory to a bit in a bit-band region of
memory.
A mapping formula shows how to reference each word in the alias region to a corresponding
bit, or target bit, in the bit-band region. The mapping formula is:
bit_word_addr = bit_ban (byte_offset x 32) + (bit_number × 4)…….(1-1)
where:
bit_word_addr is the address of the word in the alias memory region that maps to the
targeted bit.
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...