How to get into the "diagnostic mode" from Sansa Clip Zip?

[Phrenonym]

Hello,

this is my first post here.

According to the diagnostic mode of the original firmware, the display can apparently be one of two types: Visionox or WiseChip. The Visionox display could be a Visionox M00230/M00231 OLED module, the display controller is unknown. The WiseChip display appears to be controlled by a SEPS114A OLED controller. The tuner chip is the SiLabs Si4703, which is the RDS capable brother of the SiLabs Si4702 (used in several other Sansa players).

(http://www.rockbox.org/wiki/SansaClip#Sansa_Clip_Zip_port_status)

Sounds interesting. How to get into this mode? Should I uninstall Rockbox?

[EEHobbyman]

IF this is figured out I'd like to know too !!
thanks!!