| 摘要 |
PURPOSE:To decide the phase shift of an envelope of the electronic musical instrument with a small hardware quantity by comparing the output of a subtracting means with a specific constant and deciding that the conditions of the phase shift of the envelope are met when the output is larger. CONSTITUTION:The output of a selector 7 is connected to the plus side input terminal of a subtracter 20 and in attack phase, 4+4-bit floating point display data showing an attack level is inputted. The high-order 8 bits of the output of a fixed point display floating point display converting circuit 11 are connected to the minus-side terminal. Then the subtracter 20 regards respective input data simply as 8-bit linear data and subtracts them and a constant comparator 21 compares the output of the subtracter 20 with the specific constant and outputs '1' when the output of the subtracter 20 is larger. This output is inputted to a phase control circuit 18 and phase shifting operation is performed similarly as conventional way. |
