refclock: increase PPS lock limit

Increase the maximum acceptable offset of the PPS lock reference from
20% to 40% of the PPS interval to not require the refclock offset to be
specified in configuration so accurately, or enable operation with a
highly unstable reference clock.
This commit is contained in:
Miroslav Lichvar 2021-03-18 11:49:08 +01:00
parent 3812ec2aa2
commit 5381fb4ee9

View file

@ -40,6 +40,9 @@
#include "samplefilt.h"
#include "sched.h"
/* Maximum offset of locked reference as a fraction of the PPS interval */
#define PPS_LOCK_LIMIT 0.4
/* list of refclock drivers */
extern RefclockDriver RCL_SHM_driver;
extern RefclockDriver RCL_SOCK_driver;
@ -577,7 +580,7 @@ RCL_AddCookedPulse(RCL_Instance instance, struct timespec *cooked_time,
offset += shift;
if (fabs(ref_sample.offset - offset) +
ref_sample.root_dispersion + dispersion >= 0.2 / rate) {
ref_sample.root_dispersion + dispersion > PPS_LOCK_LIMIT / rate) {
DEBUG_LOG("refclock pulse ignored offdiff=%.9f refdisp=%.9f disp=%.9f",
ref_sample.offset - offset, ref_sample.root_dispersion, dispersion);
return 0;