Modifications

== L'accès mémoire (Aligned Memory Access) ==

== L'accès mémoire (Aligned Memory Access) ==

This is a little less likely to happen to you but it happened to me! If you're used to 8-bit platforms, you can do this nice thing where you can typecast variables around. e.g.

Cela ne risque pas forcément de vous arriver mais nous avons rencontré ce problème!  

 

Si vous avez l'habitude des plateformes 8-bits, vous pouvez utiliser des techniques de typecasting de variable comme celle-ci dessous:

  <nowiki>uint8_t mybuffer[4];

  <nowiki>uint8_t mybuffer[4];

float f = (float)mybuffer;</nowiki>

float f = (float)mybuffer;</nowiki>

You can't be guaranteed that this will work on a 32-bit platform because '''mybuffer''' might not be aligned to a 2 or 4-byte boundary. The ARM Cortex-M0 can only directly access data on 16-bit boundaries (every 2 or 4 bytes). Trying to access an odd-boundary byte (on a 1 or 3 byte location) will cause a Hard Fault and stop the MCU. Thankfully, there's an easy work around ... just use memcpy!

Vous ne pouvez pas avoir la garantie qu'une telle méthode fonctionnera sur une plateforme 32-bits parce que '''mybuffer''' pourrait ne pas être aligné sur 2 ou 4-octets. The ARM Cortex-M0 can only directly access data on 16-bit boundaries (every 2 or 4 bytes). Trying to access an odd-boundary byte (on a 1 or 3 byte location) will cause a Hard Fault and stop the MCU. Thankfully, there's an easy work around ... just use memcpy!

  <nowiki>uint8_t mybuffer[4];

  <nowiki>uint8_t mybuffer[4];