ARMmbed
/
mbed-os
mirror of https://github.com/ARMmbed/mbed-os.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

events: Added better handling of desynchronized timers in platform layer 

An odd bug (c0951c9) in the NCS36510 ticker code caused the timer/ticker
classes to become desynchronized. Updated the handling to not assume the
timers are perfectly in synch. This will increase the event's tolerance of
less robust platforms.
pull/3779/head
Christopher Haster 2017-02-15 10:04:11 -06:00
parent c0951c9035
commit 0949164422
1 changed files with 12 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
events/equeue/equeue_mbed.cpp
View File

@ -26,15 +26,15 @@
// Ticker operations
static bool equeue_tick_inited = false;
static unsigned equeue_minutes = 0;
static volatile unsigned equeue_minutes = 0;
static unsigned equeue_timer[
(sizeof(Timer)+sizeof(unsigned)-1)/sizeof(unsigned)];
static unsigned equeue_ticker[
(sizeof(Ticker)+sizeof(unsigned)-1)/sizeof(unsigned)];
static void equeue_tick_update() {
equeue_minutes += reinterpret_cast<Timer*>(equeue_timer)->read_ms();
reinterpret_cast<Timer*>(equeue_timer)->reset();
equeue_minutes += 1;
}
static void equeue_tick_init() {
@ -48,7 +48,7 @@ static void equeue_tick_init() {
equeue_minutes = 0;
reinterpret_cast<Timer*>(equeue_timer)->start();
reinterpret_cast<Ticker*>(equeue_ticker)
->attach_us(equeue_tick_update, (1 << 16)*1000);
->attach_us(equeue_tick_update, 1000 << 16);
equeue_tick_inited = true;
}
@ -58,8 +58,15 @@ unsigned equeue_tick() {
equeue_tick_init();
}
unsigned equeue_ms = reinterpret_cast<Timer*>(equeue_timer)->read_ms();
return (equeue_minutes << 16) + equeue_ms;
unsigned minutes;
unsigned ms;
do {
minutes = equeue_minutes;
ms = reinterpret_cast<Timer*>(equeue_timer)->read_ms();
} while (minutes != equeue_minutes);
return minutes + ms;
}