diff --git a/klippy/clocksync.py b/klippy/clocksync.py
index a2c217a08..404c5e6ae 100644
--- a/klippy/clocksync.py
+++ b/klippy/clocksync.py
@@ -5,121 +5,120 @@
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging, threading
-MAX_CLOCK_DRIFT = 0.000100
+COMM_TIMEOUT = 3.5
+RTT_AGE = .000010 / (60. * 60.)
class ClockSync:
def __init__(self, reactor):
self.reactor = reactor
self.serial = None
- self.queries_pending = 0
self.status_timer = self.reactor.register_timer(self._status_event)
self.status_cmd = None
self.mcu_freq = 0.
- self.lock = threading.Lock()
self.last_clock = 0
- self.last_clock_time = self.last_clock_time_min = 0.
- self.min_freq = self.max_freq = 0.
+ self.min_half_rtt = 999999999.9
+ self.min_half_rtt_time = 0.
+ self.clock_est = self.prev_est = (0., 0, 0.)
+ self.last_clock_fast = False
def connect(self, serial):
self.serial = serial
- # Load initial last_clock/last_clock_time
msgparser = serial.msgparser
+ self.mcu_freq = msgparser.get_constant_float('CLOCK_FREQ')
+ # Load initial clock and frequency
uptime_msg = msgparser.create_command('get_uptime')
params = serial.send_with_response(uptime_msg, 'uptime')
- self.last_clock = (params['high'] << 32) | params['clock']
- self.last_clock_time = params['#receive_time']
- self.last_clock_time_min = params['#sent_time']
- self.mcu_freq = msgparser.get_constant_float('CLOCK_FREQ')
- self.min_freq = self.mcu_freq * (1. - MAX_CLOCK_DRIFT)
- self.max_freq = self.mcu_freq * (1. + MAX_CLOCK_DRIFT)
+ self.last_clock = clock = (params['high'] << 32) | params['clock']
+ new_time = .5 * (params['#sent_time'] + params['#receive_time'])
+ self.clock_est = self.prev_est = (new_time, clock, self.mcu_freq)
# Enable periodic get_status timer
- serial.register_callback(self._handle_status, 'status')
self.status_cmd = msgparser.create_command('get_status')
+ for i in range(8):
+ params = serial.send_with_response(self.status_cmd, 'status')
+ self._handle_status(params)
+ self.reactor.pause(0.100)
+ serial.register_callback(self._handle_status, 'status')
self.reactor.update_timer(self.status_timer, self.reactor.NOW)
def connect_file(self, serial, pace=False):
self.serial = serial
self.mcu_freq = serial.msgparser.get_constant_float('CLOCK_FREQ')
- est_freq = 1000000000000.
+ freq = 1000000000000.
if pace:
- est_freq = self.mcu_freq
- self.min_freq = self.max_freq = est_freq
- self.last_clock = 0
- self.last_clock_time = self.reactor.monotonic()
- serial.set_clock_est(
- self.min_freq, self.last_clock_time, self.last_clock)
- def stats(self, eventtime):
- return "last_clock=%d last_clock_time=%.3f" % (
- self.last_clock, self.last_clock_time)
- def is_active(self, eventtime):
- return self.queries_pending <= 4
- def calibrate_clock(self, print_time, eventtime):
- return (0., self.mcu_freq)
- def get_clock(self, eventtime):
- with self.lock:
- last_clock = self.last_clock
- last_clock_time = self.last_clock_time
- min_freq = self.min_freq
- return int(last_clock + (eventtime - last_clock_time) * min_freq)
- def clock32_to_clock64(self, clock32):
- with self.lock:
- last_clock = self.last_clock
- clock_diff = (last_clock - clock32) & 0xffffffff
- if clock_diff & 0x80000000:
- return last_clock + 0x100000000 - clock_diff
- return last_clock - clock_diff
- def print_time_to_clock(self, print_time):
- return int(print_time * self.mcu_freq)
- def clock_to_print_time(self, clock):
- return clock / self.mcu_freq
- def estimated_print_time(self, eventtime):
- return self.clock_to_print_time(self.get_clock(eventtime))
- def get_adjusted_freq(self):
- return self.mcu_freq
+ freq = self.mcu_freq
+ serial.set_clock_est(freq, self.reactor.monotonic(), 0)
+ # mcu clock querying
def _status_event(self, eventtime):
- self.queries_pending += 1
self.serial.send(self.status_cmd)
return eventtime + 1.0
def _handle_status(self, params):
- self.queries_pending = 0
+ # Extend clock to 64bit
+ clock32 = params['clock']
+ last_clock = self.last_clock
+ clock = (last_clock & ~0xffffffff) | clock32
+ if clock < last_clock:
+ clock += 0x100000000
+ self.last_clock = clock
+ # Check if this is the best round-trip-time seen so far
sent_time = params['#sent_time']
if not sent_time:
return
receive_time = params['#receive_time']
- clock = params['clock']
- with self.lock:
- # Extend clock to 64bit
- clock = (self.last_clock & ~0xffffffff) | clock
- if clock < self.last_clock:
- clock += 0x100000000
- # Calculate expected send time from clock and previous estimates
- clock_delta = clock - self.last_clock
- min_send_time = (self.last_clock_time_min
- + clock_delta / self.max_freq)
- max_send_time = self.last_clock_time + clock_delta / self.min_freq
- # Calculate intersection of times
- min_time = max(min_send_time, sent_time)
- max_time = min(max_send_time, receive_time)
- if min_time > max_time:
- # No intersection - clock drift must be greater than expected
- new_min_freq, new_max_freq = self.min_freq, self.max_freq
- if min_send_time > receive_time:
- new_max_freq = (
- clock_delta / (receive_time - self.last_clock_time_min))
- else:
- new_min_freq = (
- clock_delta / (sent_time - self.last_clock_time))
- logging.warning(
- "High clock drift! Now %.0f:%.0f was %.0f:%.0f",
- new_min_freq, new_max_freq, self.min_freq, self.max_freq)
- self.min_freq, self.max_freq = new_min_freq, new_max_freq
- min_time, max_time = sent_time, receive_time
- # Update variables
- self.last_clock = clock
- self.last_clock_time = max_time
- self.last_clock_time_min = min_time
- self.serial.set_clock_est(self.min_freq, max_time + 0.001, clock)
+ half_rtt = .5 * (receive_time - sent_time)
+ aged_rtt = (sent_time - self.min_half_rtt_time) * RTT_AGE
+ if half_rtt < self.min_half_rtt + aged_rtt:
+ self.min_half_rtt = half_rtt
+ self.min_half_rtt_time = sent_time
+ logging.debug("new minimum rtt=%.6f (%d)", half_rtt, self.mcu_freq)
+ # Calculate expected clock range from sent/receive time
+ est_min_clock = self.get_clock(sent_time + self.min_half_rtt)
+ est_max_clock = self.get_clock(receive_time - self.min_half_rtt)
+ if clock >= est_min_clock and clock <= est_max_clock:
+ # Sample inline with expectations
+ return
+ # Update estimated frequency based on latest sample
+ if clock > est_max_clock:
+ clock_fast = True
+ new_time = receive_time - self.min_half_rtt
+ else:
+ clock_fast = False
+ new_time = sent_time + self.min_half_rtt
+ if clock_fast != self.last_clock_fast:
+ self.prev_est = self.clock_est
+ self.last_clock_fast = clock_fast
+ new_freq = (self.prev_est[1] - clock) / (self.prev_est[0] - new_time)
+ self.serial.set_clock_est(new_freq, new_time + 0.001, clock)
+ self.clock_est = (new_time, clock, new_freq)
+ # clock frequency conversions
+ def print_time_to_clock(self, print_time):
+ return int(print_time * self.mcu_freq)
+ def clock_to_print_time(self, clock):
+ return clock / self.mcu_freq
+ def get_adjusted_freq(self):
+ return self.mcu_freq
+ # system time conversions
+ def get_clock(self, eventtime):
+ sample_time, clock, freq = self.clock_est
+ return int(clock + (eventtime - sample_time) * freq)
+ def estimated_print_time(self, eventtime):
+ return self.clock_to_print_time(self.get_clock(eventtime))
+ # misc commands
+ def clock32_to_clock64(self, clock32):
+ last_clock = self.last_clock
+ clock_diff = (last_clock - clock32) & 0xffffffff
+ if clock_diff & 0x80000000:
+ return last_clock + 0x100000000 - clock_diff
+ return last_clock - clock_diff
+ def is_active(self, eventtime):
+ print_time = self.estimated_print_time(eventtime)
+ last_clock_print_time = self.clock_to_print_time(self.last_clock)
+ return print_time < last_clock_print_time + COMM_TIMEOUT
+ def stats(self, eventtime):
+ sample_time, clock, freq = self.clock_est
+ return "freq=%d" % (freq,)
+ def calibrate_clock(self, print_time, eventtime):
+ return (0., self.mcu_freq)
-# Clock synching code for secondary MCUs (whose clocks are sync'ed to
-# a primary MCU)
+# Clock syncing code for secondary MCUs (whose clocks are sync'ed to a
+# primary MCU)
class SecondarySync(ClockSync):
def __init__(self, reactor, main_sync):
ClockSync.__init__(self, reactor)
@@ -136,6 +135,7 @@ class SecondarySync(ClockSync):
def connect_file(self, serial, pace=False):
ClockSync.connect_file(self, serial, pace)
self.clock_adj = (0., self.mcu_freq)
+ # clock frequency conversions
def print_time_to_clock(self, print_time):
adjusted_offset, adjusted_freq = self.clock_adj
return int((print_time - adjusted_offset) * adjusted_freq)
@@ -145,25 +145,22 @@ class SecondarySync(ClockSync):
def get_adjusted_freq(self):
adjusted_offset, adjusted_freq = self.clock_adj
return adjusted_freq
+ # misc commands
+ def stats(self, eventtime):
+ adjusted_offset, adjusted_freq = self.clock_adj
+ return "%s adj=%d" % (ClockSync.stats(self, eventtime), adjusted_freq)
def calibrate_clock(self, print_time, eventtime):
- #logging.debug("calibrate: %.3f: %.6f vs %.6f",
- # eventtime,
- # self.estimated_print_time(eventtime),
- # self.main_sync.estimated_print_time(eventtime))
- with self.main_sync.lock:
- ser_clock = self.main_sync.last_clock
- ser_clock_time = self.main_sync.last_clock_time
- ser_freq = self.main_sync.min_freq
+ ser_time, ser_clock, ser_freq = self.main_sync.clock_est
main_mcu_freq = self.main_sync.mcu_freq
- main_clock = (eventtime - ser_clock_time) * ser_freq + ser_clock
+ main_clock = (eventtime - ser_time) * ser_freq + ser_clock
print_time = max(print_time, main_clock / main_mcu_freq)
- main_sync_clock = (print_time + 2.) * main_mcu_freq
- sync_time = ser_clock_time + (main_sync_clock - ser_clock) / ser_freq
+ main_sync_clock = (print_time + 4.) * main_mcu_freq
+ sync_time = ser_time + (main_sync_clock - ser_clock) / ser_freq
print_clock = self.print_time_to_clock(print_time)
sync_clock = self.get_clock(sync_time)
- adjusted_freq = .5 * (sync_clock - print_clock)
+ adjusted_freq = .25 * (sync_clock - print_clock)
adjusted_offset = print_time - print_clock / adjusted_freq
self.clock_adj = (adjusted_offset, adjusted_freq)