diff options
-rw-r--r-- | cpu/at32ap/interrupts.c | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/cpu/at32ap/interrupts.c b/cpu/at32ap/interrupts.c index bef1f30..160838e 100644 --- a/cpu/at32ap/interrupts.c +++ b/cpu/at32ap/interrupts.c @@ -98,18 +98,16 @@ void set_timer(unsigned long t) */ void udelay(unsigned long usec) { - unsigned long now, end; + unsigned long cycles; + unsigned long base; + unsigned long now; - now = sysreg_read(COUNT); + base = sysreg_read(COUNT); + cycles = ((usec * (get_tbclk() / 10000)) + 50) / 100; - end = ((usec * (get_tbclk() / 10000)) + 50) / 100; - end += now; - - while (now > end) - now = sysreg_read(COUNT); - - while (now < end) + do { now = sysreg_read(COUNT); + } while ((now - base) < cycles); } static int set_interrupt_handler(unsigned int nr, void (*handler)(void), |