问：CPU是从双Flash存储器中的哪一个Flash启动(自举)的？
答：CPU可以从任一个Flash存储器启动。CPU默认是从较大的Flash启动，但这可以用ST的CAPS工具软件或第三方工具商的IDE改变。指定从哪个Flash启动是通过JTAG编程实现，这一设置不会因掉电而改变，除非芯片被擦除。
如果改变默认配置, 而从较小的flash启动. 这里理解为从Flash B1 启动.
1.9 FMI register description
The FMI Registers configure the size and base address of the Bank 0 and Bank 1. The address
ranges of Bank 0 and Bank 1 must not overlap each other.
The microcontroller boots from Bank 0 by default:
In the default configuration:
● Bank 0 is the Boot Bank, after reset the application program has to write the size and base
address of Bank 0 in the FMI_BBSR and FMI_BBADR registers
● Bank 1 is the Non-Boot Bank, after reset the application program has to write the size and
base address of Bank 1 in the FMI_NBBSR and FMI_NBBADR registers
Booting from Bank 1
The microcontroller can also boot from Bank 1. The selection of the Boot Bank can be modified
using the "CAP" Software Tool.
If Bank 1 is the Boot bank, after reset, the application program has to write the size and start
address of Bank 1 in the FMI_BBSR and FMI_BBADR registers and the size and start address
of Bank 0 in the FMI_NBBSR and FMI_NBBADR registers.
1.9.5 FMI Control register (FMI_CR)
Address Offset: 18h
Reset value: 0000 0008h
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Reserved WWS OMIE BEIE Res. B1EN B0EN Reserved
从这里可以看出默认只有b0是允许的(B0EN=1, B1EN=0), 那么通过CAPS修改默认启动自Flash B1,然而上电时Flash B1还不可见. 难道他是自动允许的?
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