Upgrading the Firmware on an LC4 or LC3+

These instructions are for upgrading the firmware on Light Counter LC4/LC4+ Light Integrator. The process is straightforward and takes 5-10 minutes.

Please note that this does not work with the older LC3 or LC3+ Light Integrators. The firmware can be installed on LC3+ Light Integrators only with a back-to-base upgrade.

You will need:

  • An LC4 or LC4+ Light Integrator. The model is shown in the top left corner of the light integrator’s display – either “Light Counter LC4” or “Light Counter LC4+”
  • A data logger connected to the LC4/LC4+. Please note that the old LC2 data logger does not work
  • An SD card. This should be freshly formatted and contain no other files or data

The firmware “HEX file” downloaded from further down this page

The Upgrade Process

1. Download the Firmware

The latest firmware for the LC4+ is here: Light Counter LC4+ Firmware v5.0.19

The firmware HEX file is distributed in a compressed ZIP archive. After downloading, uncompress the file (this may be done automatically by your browser), check the file name starts with your light integrator model and ends in “.hex”, then copy it to your SD card. It must be the only file on the SD card.

2. Connect the Data Logger to the Light Integrator

Connect the Data Logger to the Light Integrator, insert the SD card and switch on the power.

Warning: do not run the Light Integrator on battery power during the upgrade.

On the Light Integrator, navigate to: Settings >>> Data Logger. If everything is ready, you should see two blue buttons labelled as, “Format SD Card” and “Install Firmware”.


  • If the yellow “Settings >>> Data Logger” menu button is not visible, then the Data Logger is not correctly connected
  • If both of the SD card buttons are light grey instead of blue, then the SD card is not properly inserted
  • If the “Format SD Card” button is blue but the “Install Firmware” button is grey, then there is a problem with the HEX file, for example perhaps it has not been uncompressed from the ZIP distribution

3. Start the Upgrade

Touch the blue “Install Firmware” button. The Light Integrator will check that the HEX file is for the correct model. If the HEX file fails this check then the button goes grey and displays the label “Invalid Firmware”. If it passes the check then the button label changes to “Install Firmware”.

Touch the “Install Firmware” button. The button label changes to “Reboot to Install”. Touch it again to start the upgrade.

Warning: this is your last chance to back out before the upgrade. Once you touch the “Reboot to Install” the Light Integrator will not function normally until the firmware upgrade has finished.

4. The Upgrade

The upgrade itself is entirely automated:

  1. The Light Integrator reboots into the special Firmware Upgrader program
  2. The HEX file is rechecked for compatibility
  3. The old firmware is erased from the device
  4. The new firmware is loaded
  5. The new firmware is verified to ensure that no errors occurred during the upgrade
  6. The Light Integrator reboots and returns to its normal mode of operation. You should see the new firmware version displayed on the second line of the self-test screen

Warning: do not switch off the light integrator or remove the SD card during the upgrade. If the upgrade process is interrupted, then the device will attempt to recover when it restarts, but success is not guaranteed. In the unlikely event of a total failure, a “back to base” repair will be required.

Questions and Technical Support

If you have any questions about this process, or would like any advice, then just reach out and I will be very happy to help.