HP 71b: Oregon Digital Serial Plus II Manual

[Michael Fehlhammer]

There are different variants of protective cases for the HP 71b from Oregon Digital;
the Serial Plus II seemingly is the top version. In addition to a serial interface it has got 128 kB RAM and a single line LCD that typically is used to display a menu.
A short description of the device can be found in edition 2-3/88 of W&W magazine "Cursor".
I have got the device but unfortunately not the manual. Manuals for the simpler Serial Plus versions don't describe the programming of the LCD.
Has anyone got the manual?