z dokumentacji do star commandera:
To use the built-in drive of a C128D or an SX64 or to use the same Commodore
drive from a Commodore machine and a PC, you must execute a POKE command on
the Commodore machine:
- Commodore 64/128: \"POKE 56576, PEEK(56576) AND 239\" or simply \"POKE 56576,
199\".
- Commodore Plus4: \"POKE 1, PEEK(1) OR 1\".
- Commodore VIC20: \"POKE 37137, PEEK(37137) OR 3\".
This decouples the Commodore machine from the common serial bus, by
switching the CLK line to high. Every time you access the drive from the
Commodore machine, you\'ll have to issue this command again afterwards. Note
that the Commander decouples the PC automatically from the serial bus one
second after having completed a disk operation.