Fix volatile variable access in at91sam7s port example.

2015-01-30 20:54:48 +00:00
parent c2533b6ead
commit dd271af2ed
3 changed files with 13 additions and 3 deletions
@@ -91,9 +91,13 @@ static inline void millisecond_timer(
 static inline void init(
    void)
 {
+    unsigned int pcsr;
+
    /* Initialize the Parallel I/O Controller A Peripheral Clock */
    volatile AT91PS_PMC pPMC = AT91C_BASE_PMC;
-    pPMC->PMC_PCER = pPMC->PMC_PCSR | (1 << AT91C_ID_PIOA);
+
+    pcsr = pPMC->PMC_PCSR;
+    pPMC->PMC_PCER = pcsr | (1 << AT91C_ID_PIOA);

    /* Set up the LEDs (PA0 - PA3) */
    volatile AT91PS_PIO pPIO = AT91C_BASE_PIOA;