== Technical ==
Uses X[[XD-DDOS DOS]] v2.10 (which supports the harddisc, and additionally supports external double sided 80track disc drives). The 20MB 20 MB harddisc is split into four partitions, with drive names D, E, F, and G (drive name C isn't used here, but may be used as RAM disc, in combination with Dobbertin RAM expansion). Under [[FutureOS]] the four partitions are named I, J, K and L. The hard disc is contolled by this I/O Ports:
#FBE0 Dobbertin Harddisc Data Port
#FBE1 Dobbertin Harddisc Status, Reset