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Why do Continuum controllers go into bootloader mode?


Why do controllers go into bootloader mode?

Product Line

Andover Continuum


  • Bootloader
  • NC2
  • BCX
  • CX99xx
  • CX96xx
  • i2
  • b3


  • Continuum controller are placed into bootloader mode if they repeatedly hit a firmware level exception.
  • An exception is when the controller tries to do something that cannot be done. 
  • Some examples of an exception are...
    • A controller tries to read from memory that it cannot read from.
    • A controller attempts write to memory that cannot be written to.
  • On startup, flash generation controllers load the application from flash RAM.When they hit an exception, older, non-flashable controllers would simply clear the application software from ram, power up and wait for the software to be loaded from the front end. 
  • If there is a bad application there needs to be a means by which a user can intervene before the application is loaded so that the controller firmware can be reloaded or upgraded. 
  • When a flashable controller hits more than three exceptions within a ten minute time period the controller is placed into bootloader mode intentionally.


  • When a controller repeatedly goes into bootloader mode it is time to take a close look at environment which might be driving the controller to hit exceptions
  • A controller usually goes into bootloader mode due to environmental issues such as
    • Heavy ARP traffic
    • Controller grounding
    • Controller power issues
    • Problems with the communication bus.
  • A controller that repeatedly hits exceptions is placed in bootloader mode by design. 
  • Flashing a controllers firmware is the only way to get a controller out of bootloader mode. 
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