This documentation is designed to provide guidance to customers on how to 
upgrade the MHO900 series digital oscilloscope to the version in the 
"MHO900(ARM)Update.rar" file. 

 
New versions of firmware are available at the following website:
https://www.rigol.com/intl/products/oscilloscope/MHO900.html

[Notices]

    - Before upgrading, please carefully refer to the 
      "MHO900 Release Notes.txt" file to obtain the updated information of
      the firmware version. 
      
    - Please make sure your USB disk can be read correctly. MHO900 series 
      is required to use a USB Flash drive disk with FAT32 format. 
      
    - During the upgrade process, please do not cut off power and pull out the 
      USB disk, otherwise the instrument will fail to work normally.
       

[Upgrading Procedures]

    1. Copy the upgrade file MHO900_Update.GEL to the root directory of the USB
       storage device. 
       
    2. Keep the instrument in the power-on state, then insert the USB storage device into
       the USB HOST interface (next to the Power key). 
       
    3. After the USB storage device is recognized successfully. Click or tap the function navigation menu to select Storage to enter the Storage interface. Click or tap the Upgrade tab, and click or tap the input field of File Path to select the upgrade package from USB storage device.  Click or tap Upgrade to start upgrading.
       
    4. During the upgrade, the instrument interface will display the current 
       upgrade progress. 
       
    5. After upgrading has been completed, the instrument will restart. 
    
    6. Check whether the firmware version number has been updated 
       (click or tap Utility -> About). 
       
    7. After upgrading has been completed, perform the self-calibration 
       operation. Make sure that the instrument has been warmed up or has been
       operating for more than 30 minutes before the self-calibration. 
       
        a. Disconnect all input channels; 
        
        b. Click or tap Utility-> SelfCal, then click Start to perform the 
           self-calibration. 
           
        c. It takes about 30 minutes to perform the self-calibration. 
        
        d. After the calibration has been completed, restart the instrument.

[Troubleshooting]

    - If the instrument failed to read the upgrade file from the USB storage device, 
      please try to replace the USB storage device. 
      
    - If the problem still persists, please try to re-download the upgrade file.
    
    - If the problem still persists after performing the above two operations, 
      please visit the website int.rigol.com to find contacts in your region. 