HHCL - Handheld Code Loader
There are 3 methods to update your Handheld Firmware depending on which model you have. Some models are "Firmware Version Dependent", so be sure to check your Firmware version before attempting to update your Firmware.
Not sure what version you're running? Turn on your instrument (the splash screen will tell you). Or from the keyboard; press the Shift + System Key [8], then press the Status option from the Sub Menu keys. The "Package Version" will display your current version of Firmware.