Firmware update process

The easiest way to update instrument firmware is online:

  1. Provide the instrument with an Internet connection using Wi-Fi or Ethernet
  2. Access update screen (System settings > Update)
  3. The instrument will detect the latest firmware version, follow on-screen prompts to download and install the update

Updating an offline instrument is accomplished with the following steps:

  1. Click on the desired version number below. This is a link to the .lsfw firmware update file
  2. Copy or save the .lsfw file onto the root directory of a USB flash drive. Make sure it is the only .lsfw file in that location
  3. Plug the flash drive into the USB-C port on the back of the instrument, if you don't have a newer flash drive with a USB-C connection, use the adapter that was supplied with the instrument
  4. Restart the instrument to be given the option to perform a firmware update.
  5. Disconnect the USB flash drive once the update is complete

M91 firmware changelog

Rev 1.3.20191119x - 2019-11-19


  • Zero and negative field values can be entered for DC Hall and FastHall applications
  • Improved measure autorange setpoints to enhance measurement linearity

Rev 1.3.2019091701 - 2019-09-17


  • Default sample thickness setting now dependent upon if resistivity measurement was run prior in sequence or not
    • DEFault = Set to 0 m if resistivity test not run (added)
    • DEFault = Set to measured resitivity result (no change)


  • Incorrect displayed measurement range (not identical to programmed range in all states)
  • Improved error messaging when user entered sample thickness is invalid value or format

Rev 1.3.2019080101 - 2019-08-01


  • When using optimized setting and in voltage source mode, improved range and compliance auto parameter selection


  • Improved functionality when cycling into and out of sleep mode

Rev 1.2.2019053002 - 2019-05-30

Initial release