Many thanks to the ingenious developer and tinkerer @crazyc.

The timing with the change of the double button is done.

The SHIFT key can now be held and a character switched correctly.
The F1 to F6 buttons are ok. ESC exactly ok!

Now I have reworked the MATRIX. The CTRL function is missing at the moment.
I have sent the source @rfka01 for verification - the alphatp3 works great for me!

We just do not have a CURSOR in the emulation here.
I think there might be something missing on the display chip connections.
The Registe MAP is in the area 03FF0-03FFFh only as a write option.
The MOS software may use the registers for the cursor positions, red and write mus have a way.