I was also recently given a 2648, in excellent condition.
I have documentation for the 2649, and its fairly clear what sub-set of
features
are present on the 2648.
Limited IPL drivers already exist (but are not on the web site yet). A full
set of
IPL drivers for the graphics functions are being developed.
Its kinda odd how these terminals 'wake-up' with the text input directed to
the
graphical display rather than the alpha display layer. Makes looking at
directories
after cold-booting painful, so I had to write the basic terminal mode
control code
right off the bat.