Updating firmware on SDC21XX through code

I am writing a program that will configure the controller from linux, and I need to be able to reset the firmware version. I would like to do this through commands and not any additional utility.

For example in dev.roboteq.com/dev1/index.php/forum/11-...remarks?limitstart=0 , it is necessary to use minicom and then to send "w" until it "enters programming". what does this mean? I would like to avoid a solution that requires me to press w until something happens.

Is there a command that will prepare the controller to receive a firmware upgrade directly? should the file be sent using YMODEM?

Thank you