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Brain status after boot

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Brain status after boot

To summarize, the Flash memory array in Brain is divided in two blocks:



The information block: this section is reserved by STMicroelectronics to store

manufacturing information and proprietary boot code.



The main Flash memory containing the customer program and data. This corresponds

to the Flash mentioned throughout this document.

When the reset is released, Cortex-M0 starts to execute the STMicroelectronics proprietary

code in the Flash information block.

Then, this boot code copies the vector table from the main Flash to the RAM bank 1 base

address and transfers the execution of the code to the customer’s application. In order to

execute this step, the vector table of the customer’s application must be present at the start

address of the main Flash as specified in Table 2.

The default settings in order for Cortex-M0 to drive the main Flash to execute customer

code are indicated in Table 3.

Table 2. Customer code inputs to provide

Address where customer needs to put information

Information to provide

0x1001_0000 - 0x1001_00C0

1. See “Interrupt vectors” table in the Brain reference manual, Interrupt chapter and in the “Cortex-M0 Devices Generic User

Guide”, §2.3.4 for more details.

Table 3. Default device settings after boot

Parameter

Description

Value

REMAP

Indicates if main Flash or ECC RAM bank 0 seen at

address 0x1001_0000

‘0’ (if main Flash seen at address

0x1001_0000)

Clock tree

System clock source

Processor clock

80 MHz internal RC

System clock / 5 = 16 MHz

ECC RAM bank 0

Error code correction mechanism

ON (but RAM not initialized)