advanced multi-pattern handling:
The first up to four patterns can be loaded together with START and will
then form one big pattern which's parts are played / displayed alternating. Back in
the main menu, the number of the current part is shown in the upper left corner. To
edit a certain part, wait till it is played and then enter the pattern editor. The number
of the pattern to edit now appears below the playing pattern's number.
A + DOWN on any of the loaded patterns saves the whole structure. To
deactivate this "macro" mode, move the cursor to pattern zero and press
START again.
