TRIPLES LFO Eurorack Module (Shameless Selfpromotion ahead!)


What did you change? :wink:
Most of the Code in the main: Event loop is for rendering the Waveforms and handling UI so if you fuck up something there its only executed on demand…. and only if the correct LFO is selected.

The actual LFO CV is generated in the interrupt: Routine thats called by a (“the”) Timer and runs 3 16 Bit Phase Accumulators + the Lookup from RAM -> pwmOut Code.



Well for example i can set:
SYMBOL SHmultiply_Constant=2000
(instead of 2) and it doesn’t really seem to change?
i was also messing with the timer value to see if i could change the speed the module is running at. I think this changes things but still leaves me with the same range…
I’ll dive into this another time…



If you lower the settimer 65450 Value you prolong the interval in which the Phase Accumuator is updated - i would not recommend changing this, instead use a lower tempo_inc (which is then copied into lfX_PhaseInc.

You can change SHmultiply_Constant to any value you like…. first, you only will notice in S/H Mode and second if its to high, it will simply wrap around (thus produce a smaller number). Keep in mind you are limited to BYTE (256 Values) or WORD (65536 Values) Variable for Maths on a PICaxe, if you hit the upper/lower Max Value the variable will wrap around - which really is convenient if you use a Phase Accumulator :wink:



I guess i have to dive in deeper to understand what exactly it is that sets the borders for the frequency range…
I’ve got the Vanilla firmware back up now…



Do you need general advise on how the Phase Accumulator works?
“I feel an Essay coming on….” - Colin Fraser



I haven’t googled ‘phase accumulator’ yet so I won’t hold you from your essay…
I had another idea that I could introduce 3 different constants in the code and have the 3 lfo s working in a different range. That would be the dirty trick.
Other trick would be to introduce a ‘long press’ for a different constant.



Do as you like - its open source :wink:



hi there friends,

Sorry to dig up this old post, but I got a PCB set from Frank back when these were being made and I am finally getting around to finishing it. I got it just as a PCB/panel set and planned to program the PIC myself, but then put all my synth DIY projects on long term hold due to other life obligations.

Does anyone still have the Triples file that I need to load onto the PIC? I can’t seem to find it on @fcd72 website or a github anywhere. Maybe @shiftr has it?

Also, if anyone has the d:machinery Dual Bernoulli Gate PIC file, I’ll also be searching for that soon, as well! :smiley:



I still should have it somewhere I think…
I’ve been mangling with the triples code back in the day to make longer lfo s.
The triples is still my favorite lfo.
I’ll have a look. My bernouli gate malfunctions… It’s been in the repair box for a long time.



@shiftr that’d be great if you can find it! If your modified code is available I’d be happy to use that, too. I like the option for long/slow LFOs anyway.


#71 (12.8 KB)
found them…

I tried making longer LFO’s but Frank advised against it… It’s only 8 bit so if you make the LFO’s really slow you really start to hear the steppiness.

There are a few different versions of the firmware that i could find. It’s really simple and self explaining i thought when i was working on it.

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Thanks so much! Really appreciate it. Lemme know if you ever need a shipping favor or something from an American :sunny: