git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@617 35acf78f-673a-0410-8e92-d51de3d6d3f4

2009-01-11 10:28:46 +00:00 · 2009-01-11 10:28:46 +00:00 · ce006bda5a
parent 122015057a
commit ce006bda5a
1 changed files with 5 additions and 1 deletions
--- a/ports/ARM7/chcore.h
+++ b/ports/ARM7/chcore.h
@ -142,7 +142,11 @@ typedef struct {
 * IRQ prologue code, inserted at the start of all IRQ handlers enabled to
 * invoke system APIs.
 * @note This macro has a different implementation depending if compiled in
- *       ARM or THUMB mode.
+ *       ARM or THUMB mode.
+ * @note The THUMB implementation starts with ARM code because interrupt
+ *       vectors are always invoked in ARM mode regardless the bit 0
+ *       value. The switch in THUMB mode is done in the function prologue so
+ *       it is transparent to the user code.
 */
 #ifdef THUMB
 #define SYS_IRQ_PROLOGUE() {                                            \