atom Posted July 23, 2006 Report Share Posted July 23, 2006 I'm getting sme problems with my core1) The PIC is alive, sends the upload request every 2 sec2) The LED on the input port flickers on MIDI IN events3) the MIDI DEBUG test1 - LED is lit but does not flicker on SysEx events sent to the core4) the loopback test - events are coming IN (checked with a led), but not coming out I noticed with my multimeter, that a MIDI event causes the meter to beep (diode test) on an event i checked the path and up until the optocoupler it's the same beep, but after the optocoupler and on the PIC it's silent, i dunno if this test should pass the MIDI events unaltered, or do they change in some way? i didn't do the standalone optocoupler test cause i don't really understand itany help welocmed, thanks. Quote Link to comment Share on other sites More sharing options...
OrganGrinder Posted July 23, 2006 Report Share Posted July 23, 2006 hi atomhave you checked that the optcoupler is oriented the right way? i noticed on the schematic and with smashtv's cores that the optcoupler is oriented in the opposite direction to the pic (i'm going by the direction of the orientation notch on the chips)hope this helpsOrganGrinder Quote Link to comment Share on other sites More sharing options...
atom Posted July 23, 2006 Author Report Share Posted July 23, 2006 i did the optocoupler test, and1) after connecting the LED to to pins 26 and 32 of the PIC the diode lights up2) a connected the MIDI IN and OUT socket pins like on the diagram (led still on)3) i tried grounding the pin (COM input of my multimeter), the led still onand i checked the optocoupler position, it's ok (opposite to the PIC the dot of the PIC isupper left and the opto is lower right) Quote Link to comment Share on other sites More sharing options...
audiocommander Posted July 23, 2006 Report Share Posted July 23, 2006 Hello atom,dunno if get your problem, but maybe it helps:1) if u get an upload request, you should upload MIOS and an application. To my understanding no loopback is active when there is just the bootloader active2) the flickering of the input LED seems perfectly right3) sorry, never heard of the MIDI DEBUG test1- LED :-[4) is it because you want to build a Midibox Link (Linking multiple Cores)?. If so, you have to enable the link in the application you use (eg MB64) or - if you are writing your own app - implement the forwarding by yourself. See this example (forwarding CH1-events): http://www.ucapps.de/mios_c_forward_chn1.htmlRegards,Michael Quote Link to comment Share on other sites More sharing options...
atom Posted July 23, 2006 Author Report Share Posted July 23, 2006 the CORE is not getting anything on it's INPUT, it's sending but not receving (can't uploadanything, instead of checksums i get upload requests on every sent data chunk)the debug test1 is this http://www.ucapps.de/mbhp/mbhp_core_midiin_debug.gifthe loopback test is with the PIC off the socket and when the TX and RX are connectedso everything that comes in should go out (that's not working). Quote Link to comment Share on other sites More sharing options...
atom Posted July 23, 2006 Author Report Share Posted July 23, 2006 just an update:1) the MIDI event goes on the input (the multimeter beeps on every event)2) it passes the diode D1 (beeps on both diode ends)3) the input pin of the optocoupler has the signal (when connected t the optocoupler pin, the meter beeps)4) when connected to the output of the optocoupler no beeps, the voltage between IC2::5 and IC2::8 is 5Vbased on this ca i assume that the optocoupler is broken(i've been playing around with the MIDI input polarity alot, trying to figure out witch is rightand someone on the forum wrote that wrong polarity can break the optocoupler) Quote Link to comment Share on other sites More sharing options...
TK. Posted July 24, 2006 Report Share Posted July 24, 2006 There is an optocoupler test which allows you to check, if it is really broken:Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
atom Posted July 24, 2006 Author Report Share Posted July 24, 2006 yeah that's the only one i didn't do cause i don't have the spareresistors and no vectorboard to attach it, but i'm on my way to thestore today to get that stuff and will test it, also i'll get a coupleof spare optocouplers anyway.thanks for the help, hope i'll manage to get it working. Quote Link to comment Share on other sites More sharing options...
atom Posted July 24, 2006 Author Report Share Posted July 24, 2006 i got a new optocoupler and still no luckwhat should i be reading on the optocouplers output ?is there some way i can find out if it's passing the MIDI messageswhat does it do in practice ? i don't know what to do now, maybei'm looking in the wrong place, and the optocoupler was ok anyway?i'm kinda stuck i'd appritieate some practical advice on how to debug this problemthanks. Quote Link to comment Share on other sites More sharing options...
TK. Posted July 24, 2006 Report Share Posted July 24, 2006 Is this test working?if not, you propably missed to solder a pin, or there is a short at the bottom of the PCBBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
atom Posted July 24, 2006 Author Report Share Posted July 24, 2006 i'm sorry bad i'm very unsure if im reading the test schematic righti tried drawing what i'm wiring, the led+res on the pic is connected to pins 26 and 31 likei drew, and the pins of the MIDI i/o are shortened like above, the LED lights upbut does not turn off when i connect ground to the MIDI IN pin (the other one)is this the right "diagram" for this test ?(sorry for the childish drawings but i'm very "green" when it comes to electronics) Quote Link to comment Share on other sites More sharing options...
TK. Posted July 24, 2006 Report Share Posted July 24, 2006 Your drawing looks correct, there is only one error, but I guess that you've considered this: the polarity of the LED is wrong.When the LED is permanently on, it has the same effect like if the optocoupler is not in the socket (you can remove the opto in order to doublecheck this behaviour). This would identify again, that there is a connection problem (did you check the bottom of the PCB?)And another hint: check the polarity of D1Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
atom Posted August 15, 2006 Author Report Share Posted August 15, 2006 I still can't get it to recieve MIDI, i took some pics of the board(poor qulaity i need to get a good camera ad repost asap)FrontBacki tried the loopback test again and it failed, when i took the opto out of the socketand connected the in and out pins of the the optocoupler the loopback was fine (only i had to connect the remaining MIDI pins with each other otherwise it would not work J12 M- to J13 M- were connected and pins 2 and 6 off the OPTO were connected). When i put the opto in the socket no go (i have +5V between pins 5 and 8 of the opto). I don't know how to check the diode (if it's not broken), i have a digital multimeter with a diode teseter but since i'm a complete n00b in diy electronics i don't know what sould it be showing in both directions of the diode (any help here?). Quote Link to comment Share on other sites More sharing options...
TK. Posted August 15, 2006 Report Share Posted August 15, 2006 When the ground of your tester is connected to the cathode (pin marked with the black line), and + with the anode, it should beep (or show the current draw if no accoustic signal is available). If you test it in the other direction, it should not "beep" (-> no current draw). Unfortunately on your pictures the direction of the diode cannot be regognized, but I guess that you've already doublechecked this with my pictures?In the last months, we had several users who reported problems with the MIDI interface of their mainboard. I noticed, that you haven't mentioned yet, which kind of MIDI interface you are using...?Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
atom Posted August 16, 2006 Author Report Share Posted August 16, 2006 I'm using MIDISport 4x4 with M-Audio, though i can use- M-Audio Ozonic - Echo Audiofire- onboard Asus interface(the midisport is the simplest to use for me) Quote Link to comment Share on other sites More sharing options...
TK. Posted August 17, 2006 Report Share Posted August 17, 2006 With the MIDIsport 4x4 (and 2x2) normaly no problems have to be expected - hardware & driver work very stableBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
c0nsumer Posted August 17, 2006 Report Share Posted August 17, 2006 With the MIDIsport 4x4 (and 2x2) normaly no problems have to be expected - hardware & driver work very stableFor what it's worth, I regularly use a MIDIsport 2x2 under Windows XP and OS X with my MIDIbox SID and it works very well. There isn't much to say about it, really. The device just works.-Steve Quote Link to comment Share on other sites More sharing options...
atom Posted August 17, 2006 Author Report Share Posted August 17, 2006 yeah i don't think it's the midi interface, that's definetly something wrong with my core. just can't figure out what (yet :)). Quote Link to comment Share on other sites More sharing options...
TK. Posted August 17, 2006 Report Share Posted August 17, 2006 Tip of the day: did you ever check what happens when the two wires to the MIDI In socket are swapped?Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
OrganGrinder Posted August 18, 2006 Report Share Posted August 18, 2006 Tip of the day: did you ever check what happens when the two wires to the MIDI In socket are swapped?Best Regards, Thorsten.yea. I did that mistake once on a midi out, the result was no (valid) signal to the next midi device (midi studio didn't read a thing until the wires were setup correctly). no reason to believe that if swapped on midi in that a valid signal is recieved (signal on the wrong wire).OrganGrinder Quote Link to comment Share on other sites More sharing options...
atom Posted August 18, 2006 Author Report Share Posted August 18, 2006 MIDI OUT is fine from the core i'm getting upload requests every 2secit's the IN that's not working.anyway i swaped the cables, that didn't help. i have 3 optocouplers i checked themtoo (all) also nothing. i'm stuck Quote Link to comment Share on other sites More sharing options...
c0nsumer Posted August 18, 2006 Report Share Posted August 18, 2006 MIDI OUT is fine from the core i'm getting upload requests every 2secit's the IN that's not working.anyway i swaped the cables, that didn't help. i have 3 optocouplers i checked themtoo (all) also nothing. i'm stuckCheck resistor values. I made a stupid mistake once and put a 5R6 in instead of a 5K6, and thusly the MIDI IN line to the PIC stayed at a solid 5V.-Steve Quote Link to comment Share on other sites More sharing options...
atom Posted August 18, 2006 Author Report Share Posted August 18, 2006 i double checked the resistors and theyre green,blue,red,gold for R5 (5,6K)brown,red,red,gold for R6 (1,2K)at least ccording to this: http://serwis-tv.com/opornik.htmlanyway i was wondering if i wanted to go straight to the PIC ommiting the Optohow would i go about that, can i connect the midi IN pins to the RX pin of the pic ?(i know it's unsafe and propably shouldn't be done but i'll try anything) Quote Link to comment Share on other sites More sharing options...
TK. Posted August 18, 2006 Report Share Posted August 18, 2006 Yes, with MIDIsport devices it works: ground (the middle pin of the MIDI cable) has to be connected to J11:Vs, and the Tx signal of the MIDI interface (compare with MIDI Out of the core module where Tx of the PIC is connected - if you are unsure, try both possibilities) to J11:RxThe optocoupler has to be removed to avoid a short circuitBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
atom Posted August 21, 2006 Author Report Share Posted August 21, 2006 allright finally some progress, after connecting the MIDI IN (middle pin of the MIDI IN PORT and "the other" pin of the port) to the pins TK mentioned, i got the core to recieve MIDI.But i'm wondering i wasn't getting any MIDI before, but i had the MIDI port connected to the pins "besides" the middle pin of the port, and now i switched one to the middle and it works. Now when i reinstall the Opto, should i connect the pins back so that netiher pin is connected to the middle pin, or should i leave it like that? Quote Link to comment Share on other sites More sharing options...
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