A clone of a classic using my PIC code by J-P Desrochers
Jean-Pierre Desrochers wanted to copy the response of the Moog 911 envelope generator using more modern technology. He asked me if it would be possible to tweak the response of my PIC envelope generator to do this, and I told him that it would, since the control mapping is stored in a table in the code. JP worked out the required table values and a front panel design.
JP used Alpha 100K Lin pots to generate the CVs. Other potentiometers might have a different range or response and may not line up neatly with the panel graphic.
The Moog 911 code is based on my version 7 code, rather than the latest version 7B. JP disabled the TIME CV, but otherwise it is as per the original. I’ve included both his and my code below for comparison.
I improved the output filtering for the new version 7B, so if you build this, I’d advise you to use the filter from the 7B datasheet, rather than the single stage one in the datasheet below. On the plus side, the version 7 code uses an interrupt to detect GATE pulses, and so should react quicker than version 7B, which polls the input. It’ll be tiny differences though!