dubphil

Hello, I don't own a sophisticated multimeter with the beep beep feature to detect shorts, so I have stolen in my kids bedroom an awful toy that gives an horrible sound when you press a button, yeah that will do the trick ;) After having replaced the toy's button by two wires, I decided to try it on my finally buggy CORE (you can read the story here : ) . So I clamped the anode wire to the ground and used the cathode wire to make the contact on the solder joints; the result was a hurly-burly nearly everytime I made the contact to a joint. So I opened the .brd file of the CORE and drawn "in black" all the tracks and joints that are directly connected to the ground then I drawn all the tracks and joints that are connected to the ground with a composant (capacitor, resistor, etc). So finally it remains few joints and tracks to check. here is the scheme : http://migratis.net/find_short.png knowing that my problem is that I measure +5V before the R9 resistor and just after I measure 3,8V, the beep beep trick doesn't help much : around this place, everything beeps... pfiouuuuuuu electronic is the most hard discipline to learn by myself. Thanks to teach me what I can't find by myself. Best regards Philippe

My CORE seems to be ok in fact, more details here :

At the edge of the suicide, I red back this post and I feel very bad to realize that I did not tested the app you've suggested to me, so today I did, and you know what ? My CORE seems to perfectly work, if I connect J9:SI to ground all the events are sent :) So I say loud and clear to the community : we are not expected to measure 5V at J9:SI, 3.8V seems to be sufficient for the PIC to send the events. Also there is A 20 KOhm resistance between J9:SI and VS and this doesn't seem to give any trouble ;) This said, my buttons are by the way not working, so now I have to debug the DINX4 module, a step forward that's better than nothing. Thanks a lot Julien ! Philippe

good job Phil, you give me hope :) you didn't comment my experiment then, that means that it was useless to test such a thing ? I did another thing, I bypassed the R9 and now I have well 5V on J9:SI, can I leave this resistor bypassed or it could hurt something in the circuit ? Best regards Philippe

another experiment I did : I have completely scrached the track to the J9:SI joint (and also removed the J9:SI pin but this is an accident of previous attempt to reduce the solder) and measure gives always 3.8V, is this possible ? Best regards Philippe

Hi Phil, here is a pic of one of a SmashTV PCB, the traces you can see all around the solders is of course not solder, it is the transparent material that is often ejected of the solder when I burn it, do this material can make a bridge ? even if the SmashTV's PCB seems to be protected at the surface by an apparent plastic layer ? Regards Philippe

Victory ! I did rescucitation of the dead PCB. as you suggest, I followed the 5V tracks and found solder that had overflow on the top side of the pcb but hidden by the body of a capacitor. So now I have 3 CORE pcbs that shows the exactly same symptoms : j9:SI at about 3,8V with and without the PIC, 5V is well measured upstream R9 J9:SI and VS with a resistance of about 20 Ohm (the Mike PCB as suggest Phil was messy around J9, but the SmashTV one's are really not messy). I don't know why but I suspect that it is a reproductible error that I make, when I look to the SmashTV's PCB I'm more confident on the fact that the problem is not an arbitrary short won't you ? Does any arbitrary short leads to the same symptoms ? Thanks ! Philippe

yes I do and I have also connected tracks with solder and I'm unable to remove those bridges the solder is so thin than my solder pomp pomps nothing and when I scratch the bridges it lifts the tracks :( it is quite a botch work :) I use this one : http://www.lapanthera.hu/hu/doc/SOLOMON%20SR965.pdf . I don't know if it is 25W or 40W because it was part of a cheap soldering kit with pliers, wire cutters, a pomp and 1mm solder all this for only 30€ in 2005. the first one (SmashTV pcb) is definitly dead, the voltage regulator is heating like hell and no more display and midi out/in. the second one (SmashTV pcb)is always working well apart this J9:SI problem that shows less than 4V :( Yes I would very like to do such joint :) perhaps I should acquire better soldering tools, can you advice me on a good soldering iron and solder for this type of build ? Best and thanks for the time you spent to help me Phil. ps: as I was afraid and I completely understand, Mike has no time to build the unit for his customers, so I will have to struggle myself... Philippe

arf thanks Phil but I've just ruined the PCB by wanted to remove the to much solder on some joints, I will ask for Mike if he would be kind to mount it for me and I will pay the time by paypal. Thanks again. Philippe

perhaps my last chance : here is a macro pic of my CORE : http://migratis.net/core.jpg can somebody point me to the potential fault part ? Thanks in advance Philippe

You must be right it is a short, I've the same measurements without the pic. I'm damned with this CORE, I must admit that I'm not enough skilled to build such a unit : 3 builds 3 failed :( Thanks a lot Phil Philippe

Please give me some help, I'm desperate with this issue since 2005 :(

I've just test it without the pic : I get the same measurements I have reheat, traces seams to be separated (by nude eye). Something I'm not sure, is it normal to find a short between J9:SI and VS of about 15 ohm ? (it is hard to mesure this more precisely with my cheap analog multimeter) Thanks for your help jbartee Philippe

in fact with the 2 SmashTV's CORE and the Mike's CORE I've build I have the same issue describe in this post here : on the Mike's CORE I have the 5V on the postion where Törsten advice to check here : http://www.ucapps.de/mbhp_core.html I have 5v just before R9 and less than 4v after at RD1 of the PIC and J9:SI. I'm not an electronicien as you can see, and I use a cheap analog multimeter (but it show me 5v where I should find it at others points). by the way, the MIDIO128 doesn't show events from my buttons when I press them so there is something odd somewhere. Thanks again. Philippe

yeah thanks a lot jbartee ! the schematic you point me was very precious to resolve the thing, I hadn't connect the Vs pin of J5 to ground (that's was the cause of the spurious events) and I did connect the wrong pins of J5 to the the AIN module (that explain why I had a range from -64 to 63) no more missing steps all the analogic part is perfect now :) Not the same for the DIN module : after two build of the SmashTV core and 1 build of the Mike core, I have always voltage < 4V at the J9:SI pin when I use the SRIO_interconnection_testV2 (without the DIN module connected to the CORE). It would be evil that I always fall in soldering something well that would result to the same issue isn't it ? there is certainly something odd that should alert Törsten. I'm very open to check what you want me to check to find the problem, I can also send the SmashTV CORE to someone for debugging. nevertheless thanks a lot for your kind help jbartee ! Philippe

additionnal information : if I connect the unit to MIOS Studio, the range value are 1 to 126 I can't reach 0 or 127 so the range differs from the one display on the LCD. another thing I have noticed that about several cc events are happening when I switch on the unit during about 20 seconds even if I don't touch to any pots, then arbitrarily one CC event happens, the channel concerned is not always the same, And finally when I turn the pot of a channel, sometimes other channels are giving CC events, and if I leave the pots the channel continue to give CC events during few seconds. I just want to say that before building the Mike CORE V3 I have used a SmashTV CORE where Anolog input where perfectly working (unfortunatly not the digital inputs), so all the pots connections to AIN module and ground haven't been touched. Thanks in advance for your kind help. Philippe

Hello, I have just build a new CORE (V3 from Mike), and when all the stuff is connected, the pots connected to AIN J1 and J2 have range values from -64 to 63. The pots connected to J3 are showing good range values (0 to 127). I use an AIN module from SmashTV, everything seems to be well connected and soldered, where could I start to debug such a precise issue ? Kind regards Philippe

Bonjour à tous, J'arrive pas à faire fonctionner mon module DIN, j'ai procédé aux tests du SRIO interconnection test presque tout est bon sauf le PIN J9:SI qui présente une tension de 3.8V au lieu de 5V comme suggéré dans le test. je suis remonté jusqu'à la résistance R6 de 10K qui est connectée au J9:SI ainsi qu'au pin RD1 (#20) du PIC. Avant la résistance le courant qui circule est bien de 5V mais après elle descend à 3.8V est-ce normal ? Si oui comment se fait-il qu'on doive s'attendre à mesurer 5V sur J9:SI !? Là j'avoue que j'ai un problème de compréhension... Merci d'avance pour votre aide ! Philippe

As you have see, I'm not an electronician, but I recall this formula of the Ohm law : U = R*I I use a generator of 9V/500mA that is regulated to 5V I don't know if the intensity is changed by the regulator. Before the 10k resistor, I mesure a 5V voltage after the resistor I mesure less than 4V : so 4 / 10000 = 0,0004 A (0.4mA) is this possible ? suppose everything it's ok, the voltage directly after the resistor is 4V. How can I would find 5V on J9:SI pin as suggest the SRIO interconnection test !!?? Philippe

If I understand well, I have of course tested the J9:SI voltage with nothing plugged in it. if I test the voltage before the 10K R9 voltage is 5V, but if I test just after the voltage fall to less or equal to 4V is this normal ? Thanks for your kind help lylehaze. Philippe

Hello, When my pic 18F452 is plugged on its socket and the SRIO test running, the J9:SI pin is less or equal to 4V. When I check directly the #20 pin of the pic it is also less or equal to 4V. I've just tested a new pic provided by Mike, same results with older pics from SmashTV, any idea what can give this bad voltage on this pin ? I would like to make working my DIN and DOUT modules. Best regards Philippe EDIT: sorry the title is wrong I mean the RD1 pin of the pic

apparemment le problème se situe déjà en amont, quelqu'un peut-il faire ce test et me donner le résultat ? chargez le prog SRIO_Interconnection_test puis sur le pin J9/SI mesurez la tension après avoir envoyé une mod wheel de 1. moi j'obtient ~ 4V et normalement on devrait avoir 5V ce qui expliquerait que mes bouttons ne marchent pas :( par contre la cause est vraiment mystérieuse car j'ai changé le PIC au moins trois fois et j'ai refait un CORE tout neuf ! Merci d'avance ! Philippe

Oups sorry, I have already order them, I needed 20 pieces.

The Sibalco seems to be those of my mb4, but the rean P675 have the best bottom diameter for my needs... I can wait 8 weeks ;)

Thanks to all I found the Rean P675 Knob on mouser.com and they seems to sell them with no minimum quantity ;)