Topic: How do you recover a NION using "Safe Mode"?
By recovery we assume here that you somehow have uploaded a role on a Nion and that somehow the Nion is either locking up, or having spurious reboots that prevents you from "Erasing" the role from the front panel.
We don't know of any reproducible case when this might happened, but just in case you do run into this situation there is a way out !
The Nion includes a "service" menu accessible at boot time. You can access the menu by simultaneously pressing (and holding) the two buttons that are nearest to the bottom left corner and bottom right corner of the LCD display. You need to press these two buttons very early when the unit is booting and release them when you see the service menu.
Note: this menu is VERY dangerous. You can easily brick the unit by selection the wrong options, so please do not experiment, the menu was designed for the engineering team.
Anyway, in the menu, turn the wheel until "Boot Mode" is displayed, and click the wheel once. The submenu appears showing you "Normal". Turn the wheel clockwise once to have it display "Quiet" and click the wheel again. Now push the ATTN button and the unit will reboot.
This will boot the unit, but will not load the role. You can at this point "Erase" the role and (optionaly, but a good idea) reboot the unit once more (the unit will automatically be reset to the "Normal" boot mode).