A Varvara machine knows about a keyboard, a pointer device, and a NES-style 8-button gamepad, that is, D-Pad, A, B, Start, Select. The question is, how do we map all of that on a modern standard gamepad, or one of those retro emulator handhelds?
Spent a part of my restless night thinking about that. The answer is found.
The NES gamepad is mapped verbatim.
The mouse is activated by holding L2. When it is held, left stick is moving mouse, right stick is two scroll wheels, ABX are the three mouse buttons.
The keyboard is represented by a novel input method. Along the left and right edges of the screen there are vertical cards. With the left stick you select a group from the left, with the right stick you select the exact character from the group. They would be grouped per the usage frequency. To enter a character, you make a gesture with both sticks. L1/R1 would change layers. R2 would change layouts, usually languages.
This IME is slower than a regular keyboard, less intuitive than an onscreen keyboard, but 4 times more fun than either, and takes little onscreen space.