Time Sync Interface

The PC1 inside G1 features a built-in time synchronization source. Every time G1 is set to WiFi mode, this clock source performs network time synchronization. You can use Chrony (recommended) or Systemd-Timesyncd to synchronize the clock with G1’s PC1.

This document applies to G1 robots with firmware version greater than 1.5.1.

Note

Fluctuations caused by time synchronization

When PC1 performs network time synchronization, it may cause short-term time fluctuations. Therefore, it is recommended to disable G1’s WiFi mode when using programs that rely on system time.

Installing and Configuring Chrony Clock Source

First, you need to install Chrony:

sudo apt-get install chrony

Modify the configuration file /etc/chrony/chrony.conf and add the following configuration:

# Use internal network NTP server
server 192.168.123.161 iburst prefer

# If the network is not ready at startup, allow subsequent synchronization
makestep 1.0 3

# Allow hardware clock synchronization
rtcsync

# Logs (useful for debugging)
log tracking measurements statistics
logdir /var/log/chrony

Restarting Chrony and Verifying Sync Status

sudo systemctl restart chrony
chronyc sources -v

During the step of restarting Chrony, you may encounter this issue:

(base) supportcbh@supportcbh-MDF-XX:~$ sudo systemctl status chrony.service
● chrony.service - chrony, an NTP client/server
     Loaded: loaded (/lib/systemd/system/chrony.service; enabled; vendor preset: enabled)
     Active: failed (Result: core-dump) since Wed 2026-01-07 20:24:23 CST; 5s ago
       Docs: man:chronyd(8)
             man:chronyc(1)
             man:chrony.conf(5)
    Process: 36514 ExecStart=/usr/lib/systemd/scripts/chronyd-starter.sh $DAEMON_OPTS (code=exited, status=0/SUCCESS)
    Process: 36522 ExecStartPost=/usr/lib/chrony/chrony-helper update-daemon (code=exited, status=0/SUCCESS)
   Main PID: 36519 (code=dumped, signal=SYS)

Jan 07 20:24:23 supportcbh-MDF-XX systemd[1]: Starting chrony, an NTP client/server...
Jan 07 20:24:23 supportcbh-MDF-XX chronyd-starter.sh[36516]: WARNING: libcap needs an update (cap=40 should have a name).
Jan 07 20:24:23 supportcbh-MDF-XX chronyd[36519]: chronyd version 3.5 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +SIGND +ASYNCDNS +SECHASH +IPV6 -DEBUG)
Jan 07 20:24:23 supportcbh-MDF-XX chronyd[36519]: Loaded seccomp filter
Jan 07 20:24:23 supportcbh-MDF-XX systemd[1]: Started chrony, an NTP client/server.
Jan 07 20:24:23 supportcbh-MDF-XX systemd[1]: chrony.service: Main process exited, code=dumped, status=31/SYS
Jan 07 20:24:23 supportcbh-MDF-XX systemd[1]: chrony.service: Failed with result 'core-dump'.

Chrony called instructions that are prohibited by the system security filter. Solution: Disable Seccomp filtering. Modify /etc/default/chrony to fix this issue.

DAEMON_OPTS="-F 0"

To verify whether Chrony has established synchronization with the PC1 synchronization source, use the following commands.

chronyc sources -V
chronyc tracking

Installing and Configuring Systemd-Timesyncd Clock Source

Note

Mutually exclusive relationship between Chrony and Systemd-Timesyncd

Chrony and systemd-timesyncd are mutually exclusive; installing chrony will automatically uninstall systemd-timesyncd. You can switch back to the Systemd-Timesyncd clock source using apt install (not recommended).

sudo systemctl unmusk systemd-timesyncd
sudo apt install systemd-timesyncd
sudo systemctl enable --now systemd-timesyncd

Edit the configuration file /etc/systemd/timesyncd.conf with the following content:

[Time]
NTP=192.168.123.161
FallbackNTP=
PollIntervalMinSec=32
PollIntervalMaxSec=2048

Subsequently, enable and restart the service:

sudo systemctl enable systemd-timesyncd
sudo systemctl restart systemd-timesyncd

Verify synchronization status: