riot-ci/RIOT
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

atmega timer: Interrupt Pin

Browse Source 
A debug pin can be used to probe timer interrupts with an oscilloscope or
 other time measurement equipment. Thus, determine when an interrupt occurs
 and how long the timer ISR takes.
 The pin should be defined in the makefile as follows:

CFLAGS += -DDEBUG_TIMER_PORT=PORTF -DDEBUG_TIMER_DDR=DDRF \
            -DDEBUG_TIMER_PIN=PORTF4
This commit is contained in:
Josarn 2018-04-25 17:16:05 +02:00
parent d04058b54b
commit d6c0398f3d
1 changed files with 23 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
cpu/atmega_common/periph/timer.c
View File

@ -83,6 +83,21 @@ static ctx_t ctx[] = {
*/
int timer_init(tim_t tim, unsigned long freq, timer_cb_t cb, void *arg)
{
/*
* A debug pin can be used to probe timer interrupts with an oscilloscope or
* other time measurement equipment. Thus, determine when an interrupt occurs
* and how long the timer ISR takes.
* The pin should be defined in the makefile as follows:
* CFLAGS += -DDEBUG_TIMER_PORT=PORTF -DDEBUG_TIMER_DDR=DDRF \
* -DDEBUG_TIMER_PIN=PORTF4
*/
#if defined(DEBUG_TIMER_PORT)
DEBUG_TIMER_DDR |= (1 << DEBUG_TIMER_PIN);
DEBUG_TIMER_PORT &= ~(1 << DEBUG_TIMER_PIN);
DEBUG("Debug Pin: DDR 0x%02x Port 0x%02x Pin 0x%02x\n",
&DEBUG_TIMER_DDR , &DEBUG_TIMER_PORT,(1<<DEBUG_TIMER_PIN));
#endif
DEBUG("timer.c: freq = %ld\n", freq);
uint8_t pre = 0;
@ -162,11 +177,19 @@ void timer_start(tim_t tim)
#ifdef TIMER_NUMOF
static inline void _isr(tim_t tim, int chan)
{
#if defined(DEBUG_TIMER_PORT)
DEBUG_TIMER_PORT |= (1 << DEBUG_TIMER_PIN);
#endif
__enter_isr();
*ctx[tim].mask &= ~(1 << (chan + OCIE1A));
ctx[tim].cb(ctx[tim].arg, chan);
#if defined(DEBUG_TIMER_PORT)
DEBUG_TIMER_PORT &= ~(1 << DEBUG_TIMER_PIN);
#endif
__exit_isr();
}
#endif