Old x0x never been tuned (solved)

[isak]

i was right, fixed it.
running perfectly and tuned

now the midi in issue, any ideas?

[pulsar256]

As long you are getting precise note on/off events, troubles with the serial midi communications are unlikely. The IC9 latch chip could be the problem. When you say, you are not getting any high notes, I would start checking continuity from the uC on the Note 0-5 lines (especially the higher order) to the IC9. If that is all OK and the VCO itself is not having any issues anymore, the Problem will be between (and including) IC9 and the resistor network.

I Guess you could manually latch the D0-D7 Inputs of the 74AC174 (4717p in the schematics) - but those will cost you less than a buck. just pop in a new one and continue to the resistor network if that does not solve it.

[isak]

the VCO is working, no need to fix it no more, i tuned it already.

now my other problem is the midi in that donst work.
the midi thru and midi out works great but the midi in is not.

[pulsar256]

not working at all, or just sporadically / not for all notes?

edit: if it is not working at all, check the resistors, transistors and the optocoupler around midi-in: http://www.ladyada.net/media/x0xb0x/iob ... 20v1_0.png

[isak]

its not working for all notes.
i can play the midi keyboards via midi thru, that works.
in general..all the midi section is working, its probably some small thing, but what?

[pulsar256]

then trace down the midi-in signal from the io board down to the uC and if the connection is not open, the problem will be on the IO board. Could be IC24, R16, Q50 or R17. Perhaps the +5V Line.

[pulsar256]

then trace down the midi-in signal from the io board down to the uC and if the connection is not open, the problem will be on the IO board. Could be IC24, R16, Q50 or R17. Perhaps the +5V Line.

wait... if midi-thru is working and since it is connected to the same line (va R15) as your uC should be... The problem will be within that connection to the microcontroller. Let's hope the input pin is not cooked or something. You could try to listen to the digital signal using maybe a headphone jack? Measuring with a multimeter could be difficult. So my point is, if the midi line line from the IO board does not show any significant resistance on the uC input pin 10 *and* you are getting digital "noise" when picked up with a cheap hadphone it will be either the firmware or the input pin itself.

[isak]

if the midi thru is ok then IC24 is ok.
see here...
http://forums.adafruit.com/viewtopic.php?f=12&t=21479

and yet again i checked all the wires.

[isak]

When saying cooked input pin you mean pin 1 of ic24?

[pulsar256]

No, the optocoupler seems OK since MIDI-Thru is working. Check the connection to the uC (micro controller, IC3) as described above. Either it's MIDI input pin (PIN #10) is blown or the connection from the ioboard down to the uC is faulty (check for resistance between IC3/PIN10 and where Q50/R15 meet on the IO Board). If that is OK, the firmware might be also worth looking at. Check for MIDI Input channel configurations and/or update the firmware itself.

[isak]

Thanks.
I did the resistance check, it shows (-)0.4ohm.
The cable connection is ok, i reload the frimware again and still the same.
I'll replace the MC today to see if there any deference.

Thanks.

[pulsar256]

also:

(...)I would start checking continuity from the uC on the Note 0-5 lines (...= to the IC9. If that is all OK and the VCO itself is not having any issues anymore, the Problem will be between (and including) IC9 and the resistor network.

I Guess you could manually latch the D0-D7 Inputs of the 74AC174 (4717p in the schematics) - but those will cost you less than a buck. just pop in a new one and continue to the resistor network if that does not solve it.

[isak]

ok, replaced MC, didnt helped.
replaced ic9 didnt helped.

[pulsar256]

What about the built-in sequencer, is that working?

[isak]

Yes, the sequencer is fine.
Everything is working fine except the midi in.
I can move the pattern into my sequencer program, play midi when plugged into midi thru, it's synch with bpm, all is good, midi in not.

More strange things just came up...
The the decay is not working as it should, it's working but very weak not as strong as it use to be.
It's getting out of tune the next day, strange, isn't it?
Only moving tm5 just a bit and it's in tune again.