Récupérer l’erreur du quartz d’un raspberry pi synchronisé PPS

Projet: Fonctions python pour récupérer l’erreur PPM calculé par ntp entre une pps et le quartz local.

class TimevalStruct(Structure):
	_fields_ = [
		("tv_sec", c_long),
		("tv_usec", c_long),
	]

class TimexStruct(Structure):
	_fields_ = [
		("modes", c_int),
		("offset", c_long),
		("freq", c_long),
		("maxerror", c_long),
		("esterror", c_long),
		("status", c_int),
		("constant", c_long),
		("precision", c_long),
		("tolerance", c_long),
		("time", TimevalStruct),
		("tick", c_long),
		("ppsfreq", c_long),
		("jitter", c_long),
		("shift", c_int),
		("stabil", c_long),
		("jitcnt", c_long),
		("calcnt", c_long),
		("errcnt", c_long),
		("stbcnt", c_long),
		("tai", c_int),
	]
	
libc = cdll.LoadLibrary(find_library("c"))
timex = TimexStruct()
p_timex = pointer(timex)
def ntp_adjtime():
	libc.ntp_adjtime(p_timex)
	return p_timex.contents
	
def getppm():
	adjtime = ntp_adjtime()
	return adjtime.freq/(1 << 16)

class TimevalStruct(Structure):

_fields_ = [

("tv_sec", c_long),

("tv_usec", c_long),

]

class TimexStruct(Structure):

_fields_ = [

("modes", c_int),

("offset", c_long),

("freq", c_long),

("maxerror", c_long),

("esterror", c_long),

("status", c_int),

("constant", c_long),

("precision", c_long),

("tolerance", c_long),

("time", TimevalStruct),

("tick", c_long),

("ppsfreq", c_long),

("jitter", c_long),

("shift", c_int),

("stabil", c_long),

("jitcnt", c_long),

("calcnt", c_long),

("errcnt", c_long),

("stbcnt", c_long),

("tai", c_int),

]

libc = cdll.LoadLibrary(find_library("c"))

timex = TimexStruct()

p_timex = pointer(timex)

def ntp_adjtime():

libc.ntp_adjtime(p_timex)

return p_timex.contents

def getppm():

adjtime = ntp_adjtime()

return adjtime.freq/(1 << 16)