Data Sheet

I2C commands for tinyLiDAR (cont’d)

WatchDog Timer

The hardware WatchDog Timer will automatically reboot tinyLiDAR if no I2C bus activity is seen in approx 7 seconds.

This feature is essential for long term reliabilty as the watchdog timer is an independent circuit inside of the

microcontroller and can automatically reset itself if the code locks up for any reason. When the watchdog timer

triggers it will print a period on the serial log terminal output and reboot the tinyLiDAR sensor quickly. The default

mode is with the watchdog timer enabled but you can disable it using the T0 command and re-enable it with the T1

command.

T0 Disable WatchDog Timer 0x54 0x30

This command will turn off the watchdog timer in the non-volatile settings and cause a reboot. Therefore

please allow some time for it to reboot.

T1 Enable WatchDog Timer 0x54 0x31

This command will turn on the watchdog timer in the non-volatile settings and cause a reboot. Therefore

please allow some time for it to reboot.

Q Query Settings 0x51

This command will provide the current tinyLiDAR

module settings:

• Current Operation Mode: {single step or continuous}

• WatchDog Timer: {on/off}

• LED Indicator: {on/off/measurement}

• Current Preset Configuration: {HighSpeed/LongRange/HighAccuracy/tinyLiDAR

/Custom}

• Signal Rate Limit (in MCPS)

• Sigma Estimate Limit (in mm)

• Timing Budget (in ms)

• Pre Range VCSEL Period

• Final Range VCSEL Period

• tinyLiDAR

Firmware Version

• ST PAL API Version

• Offset Cal: {custom or default}

• Cal Offset (in mm)

• Crosstalk (in MCPS)

AR Auto-Set I2C Addresses 0x41 0x52

This command will set the connected tinyLiDAR(s) in a special mode where it’s possible to set their I2C

addresses by simply placing a finger in front of them. The sequence for this command is best performed with

the Arduino Terminal GUI sketch provided in Appendix A.

V Verify connected I2C addresses of the connected tinyLiDAR

units 0x56

This command was designed as a companion to the AR command above. It will search for and find all

connected tinyLiDAR

modules. It will then make their LEDs blink in sequence showing the addresses on the

terminal. Again, this sequence is best performed with the Arduino Terminal GUI sketch provided in Appendix

tinyLiDAR Reference Manual rev1.26 10