==== Bit 3 (Continue) ====
We can observe that there are only 8 resulting shapesWhen bit3 = 0, even though they volume and direction at the end of a period always are selected by using a 4-bit value.:
In other words, we have: volume = 0 shape = 1 if (ves >> 2 =direction = 0) else 7 if (ves >> 2 == 1) else ves & 7
==== Bit 2 (Attack) ====