RTC

The Axon SBC includes a hardware Real-Time Clock (RTC) based on the HYM8563 chip. This RTC allows the system to keep accurate time even when the main power is turned off and preserves system time across reboots and power cycles.

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Specification

  • Connector Type: JST

  • Pins: 2

  • Pitch: 1mm

Hardware Details

  • RTC Chip: HYM8563

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Reference/Buy RTC

User can buy Raspberry Pi compatible RTC Battery CR302 with Rated Voltage 3V (Max Voltage 3.3V )

Linux Support

To verify detection:

dmesg | grep 8563

Expected output:

rtc-hym8563 ... registered as rtc0

Usage

Check RTC time:

hwclock --show

Sync system time to RTC:

hwclock --systohc

Sync RTC time to system:

hwclock --hctosys

Notes

  • Interface: I2C0

  • Typical I2C Address: 0x51

  • RTC requires a backup battery to retain time when powered off

  • Without a battery, time will reset after power loss

  • Ensure I2C0 is enabled in the device tree for RTC functionality

Warnings

  • Ensure correct battery polarity before connecting

  • Use a compatible RTC battery with the JST connector

  • Do not exceed the recommended voltage rating