The DTV supports a PS/2 keyboard for an emulation of the original Commodore 64 keyboard. The PS/2 key mapping is hard-coded to a US keyboard layout. If you use a national (here: german) keyboard you have to translate the mapping manually.. Either by remembering the correct mapping or by painting new key caps…
Shadowolf on Forum64 presented a very nice solution: The KeyboardTwister. This small tinyAVR based HW Mod sits between the PS/2 connector of the DTV and the PS/2 keyboard and translates the keymapping.
Have a look at my KeyboardTwister gallery…