STMicroelectronics SPC572L series Reference Manual page 195

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7.4.3.6 BAF code execution begins (state 22)
After the reset signal is released to the core, BAF code execution begins.
7.4.3.7 The Core executes code to apply device setting (state 23)
The core executes BAF code written by the manufacturer to apply specific device settings to
the SPC572Lx.
The BAF code begins by initializing registers and applying device settings. The BAF code,
written by the device manufacturer, changes from device to device.
7.4.3.8 Core searches for boot header (state 31)
The core continues code execution by searching for the boot header. In the present
example, it is assumed that a valid Boot Header is present.
This is the header file that specifies which Boot CPU starts executing the user application
code.
The Boot CPU header is programmed into flash memory at the same time the user
application program is programmed into flash memory. The core searches for the boot
header, which can be located at one of four addresses:
•
0x100_0000
•
0x104_0000
•
0x108_0000
•
0x10C_0000
A valid Boot Header_ID begins with the value 0x005A.
The boot header structure consists of the following words:
1. Boot Header_ID/Boot_CPU
2. Start address
To indicate a valid boot header, the 16-bit Boot_Header_ID field is written with the value
0x005A.
Is a valid boot header present? (decision point N)
In the present example, a valid boot header is assumed to be present in flash memory.
7.4.3.9 Decode boot CPU (state 32)
The core decodes the boot header and then writes the reset vector to the Mode Entry
Module (MC_ME).
7.4.3.10 Lock BAF access (state 33)
Further access to the Boot Assist Flash is locked.
7.4.3.11 Boot from internal flash (state 34)
The MC_ME transfers the reset vector to the CPU and code execution begins at the reset
vector.
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Reset and Boot
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