Jump to content

Juel

Members
  • Posts

    19
  • Joined

  • Last visited

Posts posted by Juel

  1. That's good to know. Never heard about mil before, but I had a hard time finding

    a casing for a 8.800x1.925 meter board ;). I wonder what the HC18/U footprint of the

    crystal means. I can only find HC49/4H in my regular shops.

  2. [me=Juel]does not know the "it's working" dance, but he was smiling all

    day and felt rather confident until he hurt his fingers with a screwdriver

    while fixing a broken fan.[/me]

    FYI that fan is still broken and will forever be. >:(

    (Not smashed (no hidden anger), but surely disabled. It is also going to

    be sent back to my "supplier" for further processing. ;))

    About the scope: It is old (1978) and bad so you can't make any serious measurments

    with it, but it is a great compliment to a dmm (and FREE :)). In fact I suspected

    a bad soldering or something until I saw the waveform. Also I could trace

    the signal backwards and I was suspecting the PIC in the end, since the output was

    quite meager. But I am not sure I would ever have tried to upload the mios

    again without you guys.  :) :) :)

    Also I updated my second topic, but I don't know how to change the name to

    "Solved: ..."

    Thanks

    Juel

  3. Update

    As you can see in my other mbfm topic (Strange output from mbfm) it

    is now working.  :) :) :) The problem was a bad mios upload. So

    probably both OPL3:s were ok (since switching them gave exactly the

    same error). So I guess the YMF:s can take quite a punch before

    breaking (don't know about any long term effect though).

    Again Thanks

    Juel

  4. Working!!!!  :) :) :)

    (But noisy, almost like my sidstation.)

    I guess it must have been the mios after all.

    A bit strange since I know I would have seen

    any upload errors. And that the OPL3 module

    could have inflicted on the upload also seems

    strange, especially since I am quite sure that

    it was not connected at that time.

    So after all you were right and it was a software

    problem. Thanks a lot everyone.

    Also a great thanks to my supplier Linneberga

    (the junkyard). I think you can guess where I

    found my oscilloscope ;), in original box, with manuals.

    I don't think it was even used once.

    Thanks again

    Juel

  5. PS: Thanks for the detailed logs, that rocks.

    All information I have given is dedicated to you, since I have noticed that you usually

    remark on that ;). But then it turned out that you haven't read it all anyway :o.

    (TK seems to think it is enough though.)

    Well actually it is not true, since I am a mathematician and know exactly what you

    mean in your troubleshooting guide. If you understand the problem it is already solved.

    So you need all the info you can get.

    edit: The info is also useful for other troubleshooters.

    Ok, back to the topic. I haven't tested the mbfm app yet (currently out of electricity

    because of some maintenance work). But before that I tested the freshly uploaded

    mios and testtone, and the result was different. Apart from RC4 (RS) being 5V now

    also RC5 (WR) and RB5 (D5) were 5V (the others still 0V). I am not sure what effects

    this will have but I am moving on to mbfm test and then soldering the OPL3 again.

    Since I have changed between testtone, interconnction and mbfm apps several times

    it seems that it could be the mios upload that was corrupted (I don't recall any error

    messages though), or it could be that I uploaded with the OPL3 attached before.

    Still both of the cases seems strange.

    I'll be back when I have tested mbfm with and without OPL3.

    PS. Your info was great TK :). Especially about the testtone app. DS.

  6. I use it with both smart mode and wait for request.

    I have now uploaded mios (1.9f) and testtone(1.1d or something).

    The full logs can be found here:

    mios

    http://juel.homeip.net/midibox/mios/hex_file_upload_window.txt

    http://juel.homeip.net/midibox/mios/midi_monitor_in.txt

    http://juel.homeip.net/midibox/mios/midi_monitor_out.txt

    testtone

    http://juel.homeip.net/midibox/testtone/hex_file_upload_window.txt

    http://juel.homeip.net/midibox/testtone/midi_monitor_in.txt

    http://juel.homeip.net/midibox/testtone/midi_monitor_out.txt

    The only thing to remark is the timestamp [unknown] in the output.

    I don't know but could it be that there is no midiclock present?

    I haven't measured the outputs after I uploaded and I haven't got

    time to do it now so I will tell you tomorrow.

  7. You should use MIOS Studio, smart mode. Search for my posts about it, there are about eight trillion :D

    That is what I am using. Even without reading the posts ;) But I can add that

    I have some problem with running midiox and MIOS studio at the same time.

    Maybe I have routed wrong with midi yoke, but I don't care at the moment. It

    works fine when midiox is not running.

  8. It swallows any upload nicely without any errors. Powersupplies

    for both modules work flawless. Midi IN/OUT is "responding" as well.

    But I have desoldered the OPL3 module now so I will test again without it.

    Last time I only did uploads and it worked well with midi sending in both directions.

    I also checked with midiox that it was responding during upload. Are there any

    other miditests I could do? Also I tested the interconnections without the OPL-module,

    but the result was the same (except for perhaps a little less noise, 1-5 mV or something)

    +5V on RC4 (which should connect to IC#) and 0V on the rest. So it could help

    if someone know it the PIC sends data continously or just once during the testtone

    program.

    Finally it is only a minimal setup so I have neither LCD or LED:s. I want to get the

    synth working and try it out before I buy the expensive parts for the CS.

    Correction: The -5V mentioned above was false, I forgot to switch the scope

    to DC mode so the offset was wrong. Sorry

  9. Both soundcards where salvaged from the junkyard, and both where

    inside computerchassis. Also I never use the junkyard as a source

    when it has been raining in the last week, except for when I found

    a commodore 128. That one I found while it was raining, but it worked

    perfectly after 10 restarts (old hardware is amazing, almost like a rusty

    old mechanic machine). Actually the only thing i found and tested that

    didn't work was a SCSI harddrive that I took from a pc and used in my

    amiga. It developed a read/write error quite quickly. Regarding the

    chips it seems strange that both produce exactly the same result, which

    seems to indicate that either both are working or they have the same

    error.

    Regarding the second question I am not really sure what you mean, but

    I have followed the signal path backwards several times with both chips.

    I'm not sure if I tested the core module alone, but at least I didn't test

    it with my oscilloscope so I will desolder it asap and come back with info.

  10. I have built a minimal mbfm setup with only opl3 and core module.

    The problem is that it seemed to be completely silent until I tried it

    with my oscilloscope (I didn't use it before because it was hidden

    very carefully when we moved last time). (For all measurements

    and checks below I used the testtone program.) I found the same

    signal on all outputs and it looked approximately like this:

    output.bmp

    Before providing any data I need to point out that it is a really bad

    oscilloscope, only 10 MHz so I was astonished that it even could

    trigger on some of the signals I tested. Also all values I mention

    should are very imprecise and just approximate. 

    The output had a frequency of about 50 kHz and 10 mV peak to peak.

    The capacitors worked since there was no DC component. I then

    followed the signal path backwards through the op-amps which

    seemed to work correct.

    Now for the interesting part. The right hand side inputs on YAC:s all

    (except TST1 and TST2) had the same signal, a weaker version of the

    outputs. I don't know what all the connections are used for but it

    seems strange that all have the same values. Also everything was

    completely symmetrical over both chips and all channels.

    On the other side of the YAC:s I found a discrepancy. The DIN, or

    DOAB and DOCD had different values. Both seemed to be digital

    and both had a period of 10 us. The difference was that DOCD had

    about 0.5 us of 5V and the rest 0V, but DOAB had 2 us of -5V :o and

    the rest at 0V. Even more interesting is that this didn't change when

    is switched chips, therefore it seems that it doesn't depend on the chip.

    Appart from this SMP1 and SMP2 were identical (I just noticed I forgot

    to check CLK).

    Regarding the inputs to the YMF I have checked it with the interconnection

    test and it passed. But still the input looks weird. All connections (except

    IC#) between PIC and YMF only had a 15 MHz, 10mV peak to peak sine

    signal. Could be a disturbance but it was very steady in frequency and form,

    but sometimes a little pulsating in size (probably because of my lousy

    oscilloscope as I observed this before). Regarding IC# it was 5V but still

    with the same small sinewave overlay.

    Next step is the core module, but as the YMF is directly connected to the PIC

    I can't test the signal path any further. Still I haven't found any problem

    with it . It swallows any upload nicely without any errors. Powersupplies

    for both modules work flawless. Midi IN/OUT is "responding" as well. I

    haven't checked the oscillator on the core though.

    I would be very happy if someone has any idea of what is going on.

    Maybe someone knows what signals should be sent or at what speed.

    Also the -5V is a mystery to me (I have checked for shortscuts etc. ) and

    even more why the final outputs are all the same. If one or both of the

    YAC:s is broken they should probably not produce the same result, the

    same applies to the YMF as nothing changed when I switched it. It is also

    strange that most signals are so very faint.

    Again I have to point out that every value I have given is very imprecise,

    I would guess that for small time measurements the error is at least 20%.

    So I hope this information can be of any use and I would gladly supply

    more.

    EOF

  11. Hi, I have some trouble with my mbfm. I'm building a minimal setup with

    only core module and fm module. The problem is that it is completely

    silent. I have some ideas of what it might be, but before I start describing

    every detail I wonder if anyone has any experience with broken OPL3:s.

    Are there any typical symptoms or are they just dead?

    I wonder this because of the history of my chip(s). I salvaged some soundcards

    from the junkyard a couple of years ago (I must be psychic because I didn't know

    about this project and I always wondered why I saved ISA-cards ;)) , although I

    took them out of a computer they have most likely been exposed to a lot of moist

    (but hopefully not rain). I might add that they empty the used electronic bin quite

    often, so it is not likely that the computers had been there for more than a week

    or two. After that they have been stored in my "playingroom" in boxes and only

    touched when I was looking for some card (have helped quite a lot of people with

    my stock :)). Finally I only had an unregulated soldering iron with a max temperature

    of 450 C when i desoldered them. I was quick and and they were not even warm

    on the outside immediately after I was finished, but you never know about the

    inside.

    I have one spare OPL3, but before I switch I want to be sure there's no other

    problem.

    /juel

×
×
  • Create New...