Roland +5v trigger apps. (syncing arpegiator)

[Guest Voltrigger]

Hi,

First of all I'm very happy to find this forum.

I hope one day I will be of help as well althoug I doubt

it cause I'm not often on Internet.

(expect very long response times if you ask me something  :-/   sorry)

Now to pleasure .

I have a couple of questions to fire off:

I plan to build a one-core sid synth (20 analog pots,buttons, simple patch-display on Led-digits...)

I think I can handle that part but what I want to do

next is to add/implement the 5V trigger output of my TR-626 to be used to trigger a 'self made' arpegiator.

I have no idea about the pulse-width of the trigger

but  I have 2 questions about this :

* Do I use the DIN for the input of the sync-signal ?

If so, can I just feed the signal using a PNP with

the signal on the base and 2 pins(+-) of the DIN to the  collector/emitter? (with appr. resistors of course)?

and if so ...

* Can I use the CC-command for sending single notes, just for the 'arpegiator' and call it from the DIN-notifytoggle thingy ?

and the last thing I wanted to get verified is :

can I use the same powersupply (optimized Sid vsn)

to pre-amp a balanced Mic ? (+ - gnd)

I'm using a Sure Mic for vocoder practice on other stuff.

thanks,

Voltrigger

repeat: reply from me will take some time so sorry in advance

[TK.]

Hi,

the DINs are scanned every milisecond, so if the pulse width of the clock out isn't long enough, then you could use an external monoflop to enlarge the pulse.

Better solution: take a look into the j5_din_v1_3.zip example, it explains how dedicated input pins can be captured. It's not limited to J5, you can use any free IO pin. The example shows, how to hook the capturing routine J5_DIN_Update to the SRIO driver, but you can also call it from USER_Tick for a higher update rate. 300 uS should be adequate enough.

The J5_DIN handler will call USER_J5_DIN_NotifyToggle on every change which is comparable with the common DIN_NotifyToggle callback. Of course, you can send CC events from this function.

Powersupply: balanced supplies should be seperated from digital units, so I cannot suggest to mix these voltage domains.

Best Regards, Thorsten.

P.S.: I will move this topic to the MIOS section since it's especially interesting for programmers.

[Guest Voltrigger]

TK,

a satisfying answer   ;D

I'll have to look up that monoflop circuit though,

but if the signal was used to sync arps on Roland Juno-6 and others , then I suppose there is no need for it.

thanks!

VT

[Guest Voltrigger]

little update (no real need to reply unless you find some critical mistake...) :

for the moment I'm still waiting for my first PCB's to arrive but I've been studying the MIOS and Core business and I think I blew the horn to quickly when I said I could handle it  :-/

Not the programming but the actual hardware, especially the J5 thing that TK explained.

before I blow up 2 valuable PICs I want to be sure about one thing : how do I feed the pulse to one of the pins, or better yet, what triggers a 'toggle' ?

From what I see in the PDF File in the J5_Din example the pins are High by default and when one of the pins gets 'low' it means it was toggled.  

(right? right?)

So I did a little testing in CircuitMaker(Protel Technology)

and came up with a circuit that would lower the voltage on the J5 input pins to 0.15 volt using a NPN-transistor with

* the pulse on the Base(with a 220ohm resistor between it, or not?),

* the Vd(5 volt) on the Collector (behind the 10K resistor) and

* Vs (ground of J5) on the Emmiter.

I don't have any ftp-space so I can't post any screenshots but if anyone wants to try and experiment

with this lead, go ahead.

appart from the pulsewidth I do not see any issues but

if anyone can tell me by heart if it doesn't make ANY sence, i'm open for criticism so HIT ME!!!  ;)

Circuitmaker Student Version can be downloaded from

http://www.altium.com/circuitmaker/downloads/student.htm

more stories comming up after Xmas season.

[TK.]

Hi,

you wrote that your synth has a 5V trigger output, so thats fine, you can connect it to a IO pin of the PIC directly.

The purpose of the 10k resistor is to have some kind of default logic-level when nothing is connected to the input. This ensures plug-and-play (or better to say: "unplug and no random MIDI triggers")

Your suggested transistor circuit is not required. But btw.: it would also work in this way (but it's better to use a 1k resistor at the base input)

Best Regards, Thorsten.

[Guest Voltrigger]

Aaaahhh, if only life in general was so simple ...  ;D