I have assemble both boards, run my first test and LED 3 & 7 light up ok. However when I press switches and play with rotary all LED’s appear to work apart from 1 & 2. I had e checked the obvious and there doesnt appear to be any dry joints, everything appears to be correctly orientated and I don’t think I have burnt out the LED whilst soldering (my soldering is pretty good)…any ideas?
Also I have tried to plug in midi and audio jack to get some sound but nothing.
Also I have the Male/male connector for ISP (2x3) left on my table and not soldered to any board as I did not read any instruction on it. I can see the obvious place it should be (between rotaries 2 & 3) labelled AURISP. Should I solder this in? If so which side of the PCB? Would this component prevent any sound or LED 1 & 2 from working?
ANy ideas or help would be greatly appreciated.
Thanks in advance.
OK update…I now have sound, Shruthi is responding to midi out from both my master keyboard and sequencer program (ableton).
Outstanding issues are LED 1 or 2 still not working and I am still unsure what to do with Male/male connector for ISP.
you only need the 2x3 ISP header if you like to flash the chip with an AVR programmer. it belongs on the upper side (i.e. the long end where it says AVRISP) so you can access it from above. it has nothing to do with the sound however.
do the buttons and encoder function correctly, apart from the LEDs?
Thanks roach, all clear now on the 2x3 header (I will leave it off)
All rotaries appear to function ok and I am getting a reading of 4.92 v across all buttons with my meter but I am unsure as to if button 1 (on far lefthand side) is functioning as I have not yet put on the LCD to complete assembly. LED’s 1 & 2 still not lighting up?
Have you checked the voltage at the LED legs and that the legs are the right way around?
Yes legs are orientated the correct way around. Voltage on LED’s working reads: -0v on negative leg & 2.07v on positive leg. LED’s not working have reading of 0.
The LED is simple dead. Try with putting a second one with the pins of the soldered.
When you press S1, do all the leds except 7 turn off?
If so, you can try turning the knobs while playing, if you notice some changes in the sound your problem is definitely related to the leds. It can be an isue with the 74hc595 one 220 resistor or the leds.
I haven’t had a LED go dead on me except when putting a too high current thru it.
A dead LED it could be as all buttons are working ok. Will try a new LED, anyone have a recommendation? I know its a 3mm green but thats all, anything else I need to know to obtain a correct replacement LED?
Get a few different ones, or look in the BOM (Bill of materials) on the build page for the digital board.
Try not to go overboard on the power of the led, you don’t need 10-20.000mcd burning your eyes out
I’ve already destroyed some blue leds just because they seem to be very sensitive to heat and static electricity. I have never destroyed an old-fashion led because of those reasons.
if the switches work and you’re able to alter the oscillator settings, try to reheat all pins involved from the leds, through the 2 resistors on the left to the IC 595. maybe it’s just a cold joint and you don’t have to buy replacements.
rosch, I have already re-heated all pins to ensure its not a cold joint.V’cent, bill of materials only says 8 of LED (no other spec).
@MicMicMic, maybe I destroyed it with heat???.
I might grab one of these tomorrow:
Any issues with these replacements?
Thanks to all responses to my post, your advice/help greatly appreciated…
40mCd might be a bit dark and maybe you want to change all 8 to have similar ones?
Another suggestion: Solder the Connector to the LCD with the short pins, then you can hold the LCD onto the Digital PCBs Pads and see if everything works all right.
I think 40mcd is fine… If it has a 3mm size, is green, and is the lowest price offered by your store (= not a high performance, high brightness LED), it’ll work OK!
Rechecked Datasheet for my standard LEDs - pichenettes is right. Something round 40mcd seems to be standard.