SOLVED! LED and switch issue

Ok so I am at last stages here but I have an issue with switch for filter. S2. When I hit it it goes to the browse patch screen and lights up another LED. I can get to filter page if I scroll though pages with encoder and LED 3 does light up when its on filter page.

Any idea what I could have done here?

Maybe a short somewhere in the switch area of the control board. Look very carefully (with a magnifying glass) if there are no shorts between solder blobs of, The switches, the resistor network and the 74##165.

I would concur with Shiftr. It has to be some short around the resistor network or the IC

ok ill look also I have one part left that I didnt see in the instructions. Looks like it goes at AVRISP. Whats the deal with this part? It looks like a jumper terminal kinda.

It’s for connecting an AVRISP programmer for flashing the firmware in the ATMEGA. If you have a kit you don’t need it because the ATMEGA allready has the firmware on it. You could solder it for future use. Or keep it in your desk drawer.

That’s for hooking up an AVR programmer for sending new code on the microcontroller and other firmware development tasks. If you were interested in doing this you would already have recognized the header and soldered it :slight_smile:

Still cant get it to work right. All the connections look fine. When I press S2 it lights led8 and says browse patch. if I hit it again it asks to save and again compare. Also sometimes I can hold down S2 and leds 1-6 light and when I release it it goes to led 8 again asking to browse patch. It basically seems like s2 and s6 are doing the same right now. And like I said I can surf to S2 via the encoder and L3 lights up etc.

Photos of your boards?

What is the voltage on IC2 pin 3 when the switch is released and when it is pressed?

is that the second pin from top on left? as im looking at it the way the synth should sit towards the user? not sure of the number of the pins. Im guessing top left is 1 top right is 2? and so on?

also something I noticed not sure if its relevant but IC 4 was 24LC512( and labeled on the board) from my kit and the instructions seem to have had it named AT24C.

"Insert the 3 ICs (ATMega644p, AT24C and 6N137) in their sockets on the bottom side of the board. "

No problem with the eeprom, there are several variants used, you’ve got the biggest one :slight_smile:

Search for “IC pin numbering”, you’ll find useful material…

haha ok thanks I was wrong. Ok I on my voltmeter I have it set to DcV and if I touch com to ground on far left of board and pin 3 on IC2 I get 105ish Volts. With S2 held down its .5 volts. Am I doing this right? Thanks!

And when it was pressed I assumed you meant held down?

I tried resoldering all joints on both IC2 and IC3 and resistor network. Still to no avail.

I just tested the synth otherwise it works great it seems. Filters work, oscs work midi works. I can even still get to the filter page via the encoder but this issue of s2 not giving me the filter page still exists. What is the latest OS version for this synth? When it boots it tells me v0.98.

You’ve got the latest version of the OS.

This is strange… Do you a spare 74hc165 to try?

hmm was there one in the ambika BOM? Yes there is! Let me see if my mouser and Digi order I have so far have that IC and ill report back. I am building both.

I have an NXP 74hc165 from digi for my ambika sourced parts. Should I try it? The one thats in the shruthi now that I got with the kit is M74HC165b1

ok it worked. S2 now operates correctly. So the IC supplied with my kit was bad? Do I get a new one sent to me? :wink:

Also can you explain why its bad? I am curious to what could be wrong it.