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OpenLager Logging

OpenLager is a small external Blackbox logger with a micro SD card. It's useful on flight controllers without a flash chip, or when you want to log long flights at a high rate.

  • Practically unlimited storage.
  • Fast to download -- take out the card and read it on your computer.
  • Logging over a UART costs the flight controller very little CPU.

OpenLager, not OpenLog

The cheaper OpenLog looks similar but can't keep up with Blackbox data rates. You need an OpenLager.

Wiring

Three wires: 5 V, ground, and a free UART's TX pad to the OpenLager's RX. When it's powered, it starts a new log file and writes whatever it receives.

Setup

  1. On the Configuration tab, set that UART to Blackbox Logging at 2000000 baud. Save and reboot.
  2. On the Blackbox tab, set Logging device to Serial Port, and choose the logging mode, rate and data.

Use a fast card (UHS-I), formatted with the SD Association's formatter.

Card latch

Some OpenLagers have a hinged card holder rather than a push-to-eject slot, which pops open in heat-shrink. Carefully flatten the retaining pin a little so the card slides in and out.