How to clear all block programming and set the device EEPROM back to factory-default condition.
Network 8000 GCM, LCM, LNC or SIM controller including all 84xxx series, 85xxx series or 86xxx series devices.
It is sometimes necessary to manually clear the controller EEPROM.
Clear the controller's EEPROM. This is accomplished by pushing the reset button and the EE CLR button and holding both for at least 20 seconds before releasing. The reset process is complete when the top two red LEDs on the right edge of the controller begin blinking in their normal sequence (second LED blinks twice as fast as top LED). This process will clear the user programmable memory (including all block programming), returning the controller to its original factory condition.
The procedure above is excerpted from Technical Bulletin 99-27 , steps 1 and 2.