STM32 and CV OUT (AOUT_NG)

MIDIbox SEQ
1

Call me stupid, but i have a STM32 core here and bought a AOUT_NG.

Do i need a AOUT_NG for CV/GATE or not ?

And if yes, how shall that be connected ( STM32 <-> AOUT_NG) ?

And .. is the 25 PIN SUB-D within the layout of the 8xCinch to DB25 Adapters ( like on many audio stuff, and ES-1 from expert sleepers ) ?

Thanks for kind answers

jan

2

Call me stupid, but i have a STM32 core here and bought a AOUT_NG.

not stupid.

Do i need a AOUT_NG for CV/GATE or not ?

I’d say yes.

And if yes, how shall that be connected ( STM32 <-> AOUT_NG) ?

http://ucapps.de/midibox_seq/mbseq_v4_interconnections.pdf

And .. is the 25 PIN SUB-D within the layout of the 8xCinch to DB25 Adapters ( like on many audio stuff, and ES-1 from expert sleepers ) ?

dunno, sorry.

You can populate the pins with what you need/like. It’s the connection to your external CV-box. As a modular user, some additional triggers may be nice to be considered. Or some Amplification for the (rather low powered) gates from the STM32. Or somme attenuverters..

3

yep afaik you still need the aout for the CVs but the gates come from the STM32, at low level.

4

For inspiration: meanwhile I built an AOUT_NG module + two 74HC541 based buffer ICs into a breakout box.

The 25 pin female connector is compatible to my MBSID, MBSEQ V4 and (upcoming) MBCV V2

Since the second 74HC541 had 6 spare pins, I quadrupled Clock and Start/Stop signals.

But probably I will duplicate some gates later, because this is more useful (e.g. to reset analog LFOs)

Cable madness! :wink:

(MBSID in Bassline mode controls a semimodular analog synth via CV)

Best Regards, Thorsten.

5

For inspiration: meanwhile I built an AOUT_NG module + two 74HC541 based buffer ICs into a breakout box.

Inspirational indeed!

One could also think of switches connected to the AOUT_NG jumpers to switch between unipolar/bipolar..

Is the buffer actually amplifying the gates towards modular level (for the kraftzwerg) or does it function as protection for Core32’s circuitry?

btw. MBCV V2? very promising! :thumbsup:

6

One could also think of switches connected to the AOUT_NG jumpers to switch between unipolar/bipolar..

I configured my AOUT_NG module, so that CV1..4 are unipolar, and CV5..8 are bipolar.

Switches won’t really help, as the channels have to be calibrated when the voltage option is changed.

Is the buffer actually amplifying the gates towards modular level (for the kraftzwerg) or does it function as protection for Core32’s circuitry?

Both!

Kraftzwerg won’t trigger if the voltage is below 4V, and I know from the past (multiple reports) that even a PIC can be damaged due to overvoltage if a gate output is connected to a CV output by fault. It makes sense to add a 100 Ohm resistor in serial at all gate outputs to overcome this danger.

btw. MBCV V2? very promising! :thumbsup:

Just need some time to make it perfect :slight_smile:

Best Regards, Thorsten.

7

For inspiration: meanwhile I built an AOUT_NG module + two 74HC541 based buffer ICs into a breakout box.

Best Regards, Thorsten.

Hey TK,

I am building a breakout for the gates on my MBSID and MBSEQ, i would like to include the buffers like you have done. Where can i find schematics for this?

8

74HC541 connections:

Pin 1 and 19: OE# connected to ground

Pin 10: to ground as well

Pin 20: to 5V

Pin 2..9 are the inputs (connected to J5A/B/C)

Pin 11..18 are the outputs (connected to your synth gear)

Best Regards, Thorsten.