Cortex-M3 Wandering Code

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Cortex-M3 Wandering Code

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by Andrew on Mon May 21 18:35:27 MST 2012
Hi there,

   Does anyone know what happens if code on a Cortex-M3 MCU such as LPC1343 jumps accidentally to erased flash. So basically my question is how the MCU will interpret 0xFFFF op-code?
   Where can I find list of op-codes for ARM Cortex-M3 assembler instructions?

Cheers,
Andrew
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by Ex-Zero on Tue May 22 00:50:48 MST 2012
Just try it yourself :rolleyes:

Branch to an empty address with:

__asm("b 0x440");
And you will receive a Hard Fault :eek:

UM:

Quote:

Hard fault
A hard fault is an exception that occurs because of an error during exception processing, or because an exception cannot be managed by any other exception mechanism. Hard faults have a fixed priority of -1, meaning they have higher priority than any exception with configurable priority.

Appendix of UM is including a short description of instruction set.
Also you can find further information at ARM:

Cortex™-M3 Technical Reference Manual:
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0337i/index.html

Cortex™-M3 Devices Generic User Guide
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0552a/index.html

or more general Resources at 'Resources of':
http://www.arm.com/products/processors/cortex-m/cortex-m3.php
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by Pellek on Tue May 22 00:36:06 MST 2012
Hi,

In User Manual UM10360 chapter 34, you got a complete guide on cortexM3. However i think you got there the instructions list (page 647), but not the opcodes of the instructions.

Maybe on ARM website ?
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