STM32(cortex_m3) 的 Bit-Banding 该怎样理解?
原文是这样的:
Bit-Banding The Cortex-M3 memory map includes two bit-band memory regions. These regions map each word in an alias region of memory to a bit in a bit-band region of memory. 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. All the STM32F10x peripheral registers are mapped in a bit-band region. This feature is consequently intensively used in functions which perform single bit set/reset in order to reduce and optimize code size. ...... /* Peripheral address in the alias region */ #define PERIPH_BB_BASE ((u32)0x42000000)
它 举 的 例子中, 这个 PERIPH_BB_BASE ((u32)0x42000000) 是如何确定的?
这个文档 是 STM32 的 Firware library 的 PDF文件。
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