The buffer is in the LCD controller, the library does nothing but relay your commands and parameters to the controller. If you want to write to a fixed location on screen after scrolling the display from Home then you need to either track how much it's scrolled and offset your cursor, or just maintain your own buffers and scrolling code and overwrite the entire display every refresh.
Please enter a valid email to subscribe
We need to confirm your email address.
To complete the subscription, please click the link in the
email we just sent you.
Thank you for subscribing!
via Egeo 16