How to get firmware compiled code off sensor

I have a 2 chanel vibration sensor plus board PR55-81
in what langauge is the firmware written in?
I was trying to find the firmware code on the github and only found firmware update repo.

is this code public ? how can I access this code I want to understand the sensors from a lower level.

i understand if that is proprietary to ncd and cant be sharred. if thats the case how can i get the compiled binary off the sensor ?
I would rly appricate any help thank you guys for all the suport

The firmware is written in embedded C and next gen will be C++.
The firmware is proprietary and cant be shared with users.