This is a continuation of my first posting for a DM6 called:
DM6 Foot TriggersI decided to start a new thread because this will be a description of a complete project that I hope you will find interesting.
If you have read my previous thread, then you will know that I want to create a foot switch that will sound drum voices with both up and down foot movements. I have tried a number of prototypes for this, but have now decided that the way forward is to use some kind of active circuit.
While searching the net for a solution, I came across many examples of a 555 monostable timer circuit. This circuit can be made to produce a single pulse for a fixed time after a switch has closed. I stared wondering if this pulse could trigger a DM6 voice in place of the more commonly used piezo. My original idea was just to use the 2 switch inputs available on the DM6, but if my hunch was right I might be able to trigger all the voices with this circuit.
Well guess what? I was right
I constructed a breadboard circuit using a 556 chip, which contains two 555 timers and fiddled around with some component values until I got it working. It seems that the trigger inputs to the DM6 need a fair bit of voltage, somewhere around 5 volts with a very short pulse. According to the standard time delay calculations I ended up with a pulse that only lasts 200 milli seconds! That is incredibly quick.
Here is a picture of the design that is going to be used for a single foot switch. It has 2 identical circuits in it. One for up and one for down. There are 2 rotary switches to allow for the selection of DOWN - OFF -UP for 2 separate Drum voices. Here is that circuit.
I intend putting 4 of these in one interface box and have 4 footswitches plugged into it. The box will then be connected to the DM6 with a standard RS232 25 way cable. (That octopus cable is a real pain when it gets tangled up. I'll be glad to get rid of it!)
Thanks go to ccie5754 for his DM6 pin-out, which you can find at:
DM6 DB-25 Cable Pin-Out I will keep you posted as the project progresses.
Lou