Page 1 of 1

Sequencer issue (solved)

Posted: Mar 10th, '16, 12:38
by JanneI
Hi all,

I just finished building Yocto and everything else works as should, but all the leds are on and I think that the "shift" button is on all the time. I swapped IC7 <-> IC8, and it's little different, but still not working. Sometimes with a longer push the "play" button works as a "roll" button, so I'm guessing it's triggering the sequencer on-off-on-off-on-off... Could it be a faulty IC2/7/8? Or some kind of short circuit somewhere? What should I search?


Cheers,
Janne

Re: Sequencer issue

Posted: Mar 10th, '16, 15:38
by e-licktronic
Dear Janne,

Check that C1 and C2 are 22p and not 220pF.

Best regards,
e-licktornic

Re: Sequencer issue

Posted: Mar 10th, '16, 16:51
by JanneI
Thanks! I'll check them, but I'm pretty sure that I have the correct values. BTW, the sequencer works as should, so if the crystal was the problem shouldn't it affect the whole sequencer, timing etc? Because I can even program new patterns, but when I press one of the step buttons to add a step while the sequencer is running, it sets "the last step", which according to manual should be "shift+step1-16"? Also, in init eeprom -mode I only need to press start to start initializing (shouldn't it be start+shift?).

Hope this helps...

edit: Not sure if these FB videos will show correctly but here you can see how start -button works (on-off-on-off-on if pressed longer). I also was able to program that custom pattern with the buttons, even though it changed the "last step" many many irritating times :)

https://www.facebook.com/IsotaloJanne/v ... 93/?type=3


Cheers,
Janne

Re: Sequencer issue

Posted: Mar 15th, '16, 13:27
by JanneI
C1 and C2 are indeed 22pf.

I even tried with all 3 new hc165n chips, no change in action.

Still the shift button is always on, start trigger shoots rapid fire, so does the next/scale button.

What should I check next?

Cheers,
Janne

Re: Sequencer issue

Posted: Mar 15th, '16, 16:58
by JanneI
I measured the shift button, it's not +5v/0v, more like +0,5v/0v.

Re: Sequencer issue

Posted: Mar 15th, '16, 17:36
by JanneI
...and the problem was bad solder joint at R44. Now shift button works as should and start&next button "rapid fire" problems disappeared.