Atmel SAM L21 CPU startup

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rkagerer
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Posted by rkagerer: Mon. Jan 6, 2020 - 09:41 PM
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I'm reading the datasheet for the SAM L21 family and in section 9.3.4 Fetching of Initial Instructions it mentions:

After Reset has been released, the CPU starts fetching PC and SP values from the Reset address,
0x00000000. This points to the first executable address in the internal Flash memory. The code read from
the internal Flash can be used to configure the clock system and clock sources. Refer to the ARM
Architecture Reference Manual for more information on CPU startup (http://www.arm.com)

I found a PDF copy of the manual and searched the entire thing for "startup" with no hits.  While I don't have a specific question, I want to read more about the topic.  Am I looking at the right doc?  Is that a "dead reference" from Atmel?

Tags:

Atmel SMART ARM-based MCUs and MPUs, Atmel Cortex-A MPUs
Last Edited: Mon. Jan 6, 2020 - 10:08 PM
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Bronze Markawneil
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Posted by awneil: Mon. Jan 6, 2020 - 10:02 PM
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SAM chips are not AVRs !

 

You need:  https://community.atmel.com/forums/atmel-smart-arm-based-mcus

 

Top Tips:

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rkagerer
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Posted by rkagerer: Mon. Jan 6, 2020 - 10:07 PM (Reply to #2)
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Wrong forum?  Sorry, I saw several other posts about the L21 in this section hence thought it was relevant.  Thanks.

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Lajon
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Posted by Lajon: Mon. Jan 6, 2020 - 10:47 PM
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The Atmel SAM L21 implements the ARM®Cortex™ -M0+ processor, based on the ARMv6 Architecture and Thumb® -2 ISA.

 

https://static.docs.arm.com/ddi0419/d/DDI0419D_armv6m_arm.pdf

probably "B1.5.5 Reset behavior"

/Lars

 

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