# Time synchronization solution for RDK X5 without network access: RTC battery and intranet NTP

- Source: D-Robotics Developer Community
- Published: 2026-10-16T07:37:47.822Z
- RoboHot: https://robohot.news/en/items/scyuoi5kbbxjuk6xrhhyj8kfs
- Original: https://forum.d-robotics.cc/t/topic/35795

## Summary

If the RDK X5 shows an inaccurate time after rebooting without a network connection, you can connect a 2–3.3V rechargeable battery to the onboard RTC battery connector (connector 2) to keep time. After setting the time with date -s, write it to the RTC with hwclock -w, then add hwclock -s to startup so the system time is automatically written back.