OpenIMU300ZA output freezes after 1 minute (approx) when using PPS


Is the PPS signal supported in the firmware as per the documentation?

Output consistently freezes after 1 min when using the INS example App with PPS from the GNSS connected to pin 2.

Many thanks,


Hi Simon,
The PPS function will be ready in next firmware release.

@Li-YiFan thanks for your response.

Do you have a rough estimate of when the next firmware will be released?

Alternatively can you point to to the relevant code in the Beta on github so that I can investigate?



@Li-YiFan Any update on the firmware release?

@simon-rob Hi Simon, the PPS function not support in the old firmware OpenIMU, cuttently we have beta version with PPS on testing, the official firmware/doc will be released in the next few weeks.

@Li-YiFan Quite some time has passed now.. any updates on the next release?

@simon-rob Hi simon,
sorry for the late msg, we have the beta version with pps function.
In the beta version test, the time lag between PPS and IO2/DRDY(the pin in OpenIMU develop board) signals can be arbitrary between 0 and 5 ms but it should be stable after 20s or so. The open source code will be published on VS code aceinna extension.
You could test the bin file with the step as following, and please add your comments.

  1. Connect Ublox GPS receiver to the unit and provide proper default settings for protocol and baudrate.
  2. Connect 1PPS signal from Ublox GPS receiver to the unit.
  3. Connect probes from scope to 1PPS and IO2 pin. Sync from 1PPS signal
  4. Start application capture debug output

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