e-licktronic Forum

Hi guys,

Due to extreme fatigue, I forgot to solder the 74HC165N and 74HC595N ICs in the sequencer section and the optocoupler in the master section... They were just sitting on the PCB, I realised after powering up; the sequencer didn't start, not all the step buttons lit up and there was noise on the output.

After soldering them all in and powering up again the sequencer buttons now all light up and the noise is gone, but I can't flash the EPROM. When I try, the sequencer seems to start and triggers each voice on each step. The voices sound right but I can't trigger them with midi or use the sequencer properly.

I fear that my initial error has buggered up something or many things in the sequencer section. Any advice? I'm really kicking myself now. Should've had a rest!

- Dilli

After some rest I came back to it and found that I can set the midi notes in expander mode and trigger the voices from my computer but all the internal sequencer modes seem a bit buggy - their default setting is with all the drum voices being triggered on each step. I can deselect them with the sequencer but when. I go back to pattern mode, my changes are gone and all voices on all steps are being triggered again.

I'm glad I can at least sequence it from my computer and, apart from the hats and cymbal (I need to have a look inside again), the unit sounds absolutely amazing.

Do you think I could reload the software via sysex in order to unbugger the sequencer? It seems that it can run and can trigger voices, just not in the way it is intended to.

- Dilli

Dear Dilli,

Please check all sequencer parts position. Maybe you got ICs in a wrong way or diodes.
Here the Hex file if you want to Upload it again.
Do you have some picture of your built?

Best regards,
e-licktronic

Thanks for your reply.

I tried reloading the firmware but it bricked the yocto! Now I can't do anything with it and I'm extremely sad and angry. It loaded the sysex, then all the LEDs flashed twice and then nothing. I tried loading it again, but still nothing.

Please help!!!!!!!

- Dilli

Also, I did check the parts in the sequencer. All components are in the right way and all the solder joints are clean. It really seems like a firmware/eprom issue to me. Even before it bricked up, it seemed like the machine was carrying bad data, and not saving any new data.

Do you think it could be solved with new microcontroller and/or eprom chips?

- Dilli

Dear Dilli,

To uplaod the firmware you have to proceed like that:
-Turn Off your Yocto
-Push step button 1, 3 and 5 together
-Turn On Yocto while holding threes buttons.
-Leds will blink two times
-Then send Sysex via MidiOX or an other MIDI sysex sender.
-Leds will show you Upload progress.

Is it what you did?

Best regards,
e-licktronic

Yes, that's exactly what I did.

Now, if I hold down steps 1, 3 and 5 while I turn turning the machine on, it still appears to enter sysex mode and when i send the file with MIDIOX the LEDs light up as if it's receiving data but as soon as the transfer finishes, all the LEDs turn off and the unit remains unresponsive in all modes.

Any ideas?