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
@@ -65,9 +65,12 @@ static int RS485_Baud = 38400;
 void RS485_Initialize(
    void)
 {
+    unsigned int pcsr;
    /* Enable the USART0 clock in the Power Management Controller */
    volatile AT91PS_PMC pPMC = AT91C_BASE_PMC;
-    pPMC->PMC_PCER = pPMC->PMC_PCSR | (1 << AT91C_ID_US0);
+
+    pcsr = pPMC->PMC_PCSR;
+    pPMC->PMC_PCER = pcsr | (1 << AT91C_ID_US0);

    /* Disable and clear USART0 interrupt
       in AIC Interrupt Disable Command Register */