Hi
It's probably time to open up that info, and make it public.
Segway won't, so maybe I should.
There are 2 parts to the process.
Hardware
You need hardware like this, to write to and read from any iButton:
https://www.ebay.com.au/itm/Maxim-DS...R/272234494660
Plus you need software to run this hardware.
It is reasonably readily available.
Software / Data
One needs to calculate a data string to write to the iButton.
This string is a compilation of Keycode + parameters.
I have an Excel spreadsheet that can calculate this.
Contact me if you want a copy ( it is not perfect, but it does work mostly ).
Michael
www.dgbint.com