The latest firmware updates for Masterclock devices are available for download below. Review the firmware update procedure before attempting to perform a firmware update. All firmware downloads include the required updater utility. Contact support@masterclock.com for assistance.
Download the latest version of WinDiscovery (7.5.6) below to take advantage of any new features.
Units may also be shipped to the Masterclock Technical Support Department to perform a firmware update using our Return Merchandise Authorization (RMA) procedure.
Latest Release of Firmware for Listed Devices
Latest Version - 5/2025 - Version 6.2.2
- For Grand Master Reference (GMR) – GMR1000 and GMR5000 (for GMR6000, see next section)
- All NTDS, TCDS, TCD, CLD and MDN series devices
- All Countdown Controllers
- NTP100 - Please contact Support with your serial number prior to updating.
Firmware update file for all GMR6000 models
Latest GMR6000 Version - 1/2026 - Version 1.0.5
WinDiscovery (7.5.6)
WinDiscovery.exe is a Windows-based software for configuration of your Masterclock devices on an Ethernet network or via USB. It is compatible with Windows 10 and 11. The link below will download the Windows installer for Windiscovery.exe.