Comments on: Homebrew midi-cv box

By: dl6kbg

dl6kbg — Wed, 07 Apr 2010 19:25:49 +0000

Hi Robin !

I managed to add the midi-clock and start stop code so that i can sync/reset my analog clock sequencer and divider. i am not a programmer, so it was more a trial and error process for me. but it works. before i post something about it i would post it to you, so that you may have an eye on it.

Please contact my via e-mail.

Good luck with your PhD Exams.

Oliver, Dresden, Germany

By: charbot

charbot — Mon, 05 Apr 2010 14:48:11 +0000

OK. I got it… it seems a little quirky though. I needed to connect vref to +5v to get it going but after a few minutes I can disconnect the vref and it still works but only if the mod wheel is in the middle to high position..(shrug?) I have found that the decoupling caps on V+ arent necessary, and I guess are used for more accuracy. Stranger still, the circuit still seems to be fully operational even when I disconnect +5v from the DAC entirely. I guess Its getting power through SPI.
If anyone else is wondering, envelope and zeroin functions are for the bass pitch and amplitude tracker and arent used for the Midi2CV.

Robin, are all of the DAC outs used? Currently I am only getting output on VoutA=Gate and VoutB=CV. Im using a microkorg and a Sequential Prophet 600, not a TB303 so I guess Ill need to alter the Midi controller commands, right?
thanks

By: dl6kbg

dl6kbg — Sun, 04 Apr 2010 17:28:32 +0000

Hi Robin !

Good luck for your PhD exams. I advanced the code with snippets from little-scale so that i now have midi clock. in the video below you see the clock-divider and the baby8 sequencer synced to the main tempo.

Have Fun !

Oliver

http://www.youtube.com/watch?v=azEcFUJTsVE

Little Scales Midi Clock Code:

http://little-scale.blogspot.com/2008/05/how-to-deal-with-midi-clock-signals-in.html

By: charbot

charbot — Fri, 02 Apr 2010 21:31:34 +0000

So, I think my problem is with “Zeroin pin#2″ (zero crossing interupt).
Im not sure what to connect it to. Does this go to the DAC?
The rest of the connections are obvious but I am also uncertain what to do with:”ENVELOPE 0 //Analog in on Arduino to test DAC”… Should I just connect any DAC out pin to analog in #0? Sorry for being dense and asking so many question. Any help would be greatly appreciated

By: charbot

charbot — Thu, 01 Apr 2010 15:13:38 +0000

Hi everyone, Cool project, but Im stuck. I have everything wired as described in the code and data sheet, but Im getting no output from the dac. I changed the baud rate to 31250, and have the caps on the power like the data sheet recommends. I left the v ref pin #8 unconnected. Anything else (simple,stupid or otherwise) that I might be missing? Also, would someone post a brief description of functions for the dac output pins? For example, does VoutA (pin #4)supply CV and VoutB(pin#13) is GATE…etc? thanks in advance.

By: crx

crx — Thu, 25 Feb 2010 14:30:54 +0000

@dl6kbg Awesome work. Well done in getting it working, I can't remember what I connected my Vref in too. As for max4live bugs I haven't started dev work updating my patches for m4l yet as it hasn't fitted around PhD/hardware dev work recently. Expect examples and help over the coming month(s). @charlie hobbs Check the OP or docs for info, I dunno if I'm going to schematic this up on the web. Right now it just works for me and I haven't got time to take the unit apart and check my veroboard. This may change in the future pending funding opportunities... @Rab Cheers for the interest. See above.

By: Rab

Rab — Thu, 25 Feb 2010 13:16:29 +0000

Hi, is there a schematic for this availkable?

thanks

By: charlie hobbs

charlie hobbs — Tue, 23 Feb 2010 17:36:00 +0000

OK, here is what I have:

……..ARDUINO…………AD5668………………..
MIDI>>..pin 0 RX……………………………….
(via….pin 3…….>>>…pin 15 DIN……………..
..opto).pin 4…….>>>…pin 16 SCLK…………….
……..pin 5…….>>>…pin 2 SYNC……………..
……..pin 6…….>>>…pin 1 LDAC……………..
……..pin 7…….>>>…pin 9 CLR………………
……..pin 8>>pwrLED…..pin 3 VDD…>>> +5v……..
……..pin 9>>RXLED……pin 5 GND…>>> Ground…..
…………………….pins 4-7,& 10-13 >>> out….
…………………….pin8 VREF (not needed?)….

———————————————————————-
This is what is still not clear:
Envelope-0 Analog in on Arduino to test DAC >>>>conected to what?
ZEROIN 2 Zero crossing interupt (is this a pin declaration?)
GATE 0
CV 1
ACC 2
SLD 3
FILT 4

Does anyone with a little more expertise care to help fill in the pieces?

By: charlie hobbs

charlie hobbs — Tue, 23 Feb 2010 17:26:40 +0000

OK, here is what I have:

ARDUINO AD5668
MIDI>> pin 0 RX
(via pin 3 >>> pin 15 DIN
opto) pin 4 >>> pin 16 SCLK
pin 5 >>> pin 2 SYNC
pin 6 >>> pin 1 LDAC
pin 7 >>> pin 9 CLR
pin 8>>pwrLED pin 3 VDD >>> +5v
pin 9>>RXLED pin 5 GND >>> Ground
pins 4,5,6,7,10,11,12,13 >>> out
pin8 VREF (not needed?)

Does anyone with a little more expertise care to help fill in the pieces?

By: charlie hobbs

charlie hobbs — Mon, 22 Feb 2010 18:08:32 +0000

I too am having trouble with this and hopethat someone is kind enough to share a schematic or at least a verbal description of what connects to what. Ive been trying a with few different lower res (and lower priced) DACs. Are all of the necessary connections described in the code? i think that I may be missing something with just the sketch and data sheets to go by. Also, does the DAC out go directly to a audio jack, or through some kind of filter or buffer first?