debugging a soundless EMIC-2

Comments

• Ron Czapala Posts: 2,418

  2012-09-07 19:14 edited 2012-09-07 19:14

  Welcome to the forums!
  
  The datasheet 30016-Emic2TextToSpeech-v1.1.pdf says

  Power requirements: +5 VDC, 30 mA idle, 46-220 mA active (depending on speech parametersand output load)

  
  I suspect your voltage is too low. The audio output is only 300mw - try earphones...
• Poundy Posts: 15

  2012-09-07 19:29 edited 2012-09-07 19:29

  Right, the results are in, the (strikeout)answer(/strikeout; yes I know that doesnt work :nerd: ) next problem is known.
  
  First though, have you ever noticed how when you change two things at once, you're invariably going to fix the problem, and then have a 50:50 chance of picking which one was right?
  
  So all my previous tests were with the board connected with .1" header wires straight from my CP2102 to the module and speaker connected via the socket. This time I decided I'd drop the module onto a breadboard so I could firstly supplement the power, and I had a breadboard mountable connector on a speaker so I plugged that in too.
  
  Fire up the terminal and tell it to play the demo. Yep, it worked first time. Bugger. No, no, I mean yay, don't I?
  
  Anyway, so I know this now works - unplug breadboard speaker and whack the plugged one back in, play demo, nada, not a sound. So I undo the power-boost and connect the breadboard speaker again and we're still working.
  
  So, it's the socket on the EMIC-2 board that isn't working. I've looked under a magnifying desklamp and head mounted magnifyer, can't see any obvious solder problems on the three connectors, but they don't have a lot of solder visible - it's still got a small fillet ul the side ofthe leg, so not something I immediately think is worth hitting with the soldering iron. Can anyone confirm what I should see resistance wise between what pads on the socket or some other way to see if I cna figure out if there's a short or something?
  
  Oh, and thanks for the suggestion @Ron. I had run it on 5v and 3v3 before with the same result, and have done so now and both seem to work fine - on my more permanent mounting solution I will make sure I juice it up from the 5v rail though just to be sure.
• Roger Lee Posts: 339

  2012-09-07 22:59 edited 2012-09-07 22:59

  I would have never thought to run this directly from a PC. The description says it is for embedded systems.
  That means "Not a PC", right?
  Interesting to me that it works this way. Not that I'll be trying it, I still find it interesting.
• Poundy Posts: 15

  2012-09-08 04:13 edited 2012-09-08 04:13

  It's just a serial device, and PCs have had COM ports for a few years now
  
  :cool:
  
  So yes, while it may say for embedded systems, this way I could eliminate the "unknowns" of micro controller serial ports etc. Now I know what was going on I'll connect to the micro like intended :thumb:
  
  So again, anyone who has insight into what I can test on the socket would be great !
• Publison Posts: 12,366

  2012-09-08 04:40 edited 2012-09-08 04:40

  What kind of plug are you using, stereo or mono? If it's a stereo you might have the speaker connected to the Tip and Ring, and not the Tip and Sleeve (Ground).
  
  TRS Wiki here
• Poundy Posts: 15

  2012-09-08 04:43 edited 2012-09-08 04:43

  I've tried both, but the mono one certainly doesn't work...... the speaker I am now using was unsoldered from one of the mono plugs as well....
• mindrobots Posts: 6,506

  2012-09-08 05:01 edited 2012-09-08 05:01

  If it's an issue with the socket or solder joints, I'm sure Parallax would be interested in hearing from you for QC purposes. If there is a component or possible mfg process issue, they will want to know so they can resolve it.
• Publison Posts: 12,366

  2012-09-08 05:04 edited 2012-09-08 05:04

  The output connections are pretty easy to follow.
  
  

  

  
  
  Check the connections from SP+ to the connector. C38 may be open.
  
  EDIT: SP- does NOT go to the connector.

  

  

  Emic-2 Audio Out.JPG

  528 x 278 - 17K

  Emic-2 Audio Out.JPG 16.9K
• Poundy Posts: 15

  2012-09-08 05:23 edited 2012-09-08 05:23

  @publison, interesting, S- isn't connected to the connector from what you just showed me. Is there a "standard" that says whether the two spring loaded connectors in that diagram are the inner most or the outer most? Usually the tip is the positive, right, so the diagram would imply the two inner connections are the ones that should go to S+ pin, but I assume the capacitor across the line will block continuity testing while it's charged? So hard to confirm this I think :frown:
• Publison Posts: 12,366

  2012-09-08 10:50 edited 2012-09-08 10:50

  Sorry, got called away for tornado warning. All are gone for now.
  
  The SP+ and SP- are differential output from the chip, and per the data sheet that's the normal mode of operation. The jack that Joe implemented should work also.
  
  The Tip and Ring are connected together on the EMIC-2 board, so a mono plug should work just fine.
  
  I would check continuity from the SP+ to C38, and then continuity from the other side of C38 to the Tip or Ring on your mono cable.
  
  BTW, did you try some powered speaker from the jack?
• Poundy Posts: 15

  2012-09-08 17:41 edited 2012-09-08 17:41

  no, no powered speakers were used; I've only ever connected passive devices to it. I have tried old PC speakers in enclosures, earbud headphones, and several speakers from Jaycar (our local commercial electronics hardware place, similar I guess to Radio Shack).
  
  I guess I could check connectivity, but tracking down C38 is virtually impossible, there's no silk marking on the bottom of the board, and it's a 4-layer board at least and all the routing is internal and therefore not visible on the surface under the soldermask.
  
  Edit: tornado warning - wow. Glad to hear things are ok.
• Poundy Posts: 15

  2012-09-08 17:44 edited 2012-09-08 17:44

  mindrobots wrote: »

  If it's an issue with the socket or solder joints, I'm sure Parallax would be interested in hearing from you for QC purposes. If there is a component or possible mfg process issue, they will want to know so they can resolve it.

  I've put a support request through pointing to this thread too.... I just wanted thoughts first up but I managed to make more progress than I thought. A sample of 1 though, doesn't necessarily show a process issue, but might be a new test case they can consider.
• mindrobots Posts: 6,506

  2012-09-08 17:52 edited 2012-09-08 17:52

  Granted, 1 is only 1. It seems like there were a couple other boards with bad solder joints on connectors in recent threads. As good as Parallax is about QC and their internal manufacturing, I imagine that wanted know about any suspects.
• frank freedman Posts: 1,975

  2012-09-08 22:18 edited 2012-09-08 22:18

  Poundy wrote: »

  
  So, it's the socket on the EMIC-2 board that isn't working. I've looked under a magnifying desklamp and head mounted magnifyer, can't see any obvious solder problems on the three connectors, but they don't have a lot of solder visible - it's still got a small fillet ul the side ofthe leg, so not something I immediately think is worth hitting with the soldering iron. Can anyone confirm what I should see resistance wise between what pads on the socket or some other way to see if I cna figure out if there's a short or something?
  
  .

  
  Is this a surface mounted socket? If so and you can not get to all pins on it with a soldering iron, maybe reflow with an air soldering tool.
  
  FF
  
  (added above with an edit, had not intended to reply but somehow hit the wrong key. Rather than leaving a blank "Duh??" .......)
• Poundy Posts: 15

  2012-09-09 03:02 edited 2012-09-09 03:02

  frank freedman wrote: »

  Is this a surface mounted socket? If so and you can not get to all pins on it with a soldering iron, maybe reflow with an air soldering tool.

  It is a surface mount socket but the flat legs are ~4mm long so are big enough to hit with a soldering iron, if that's what I should do..... not ready to try that just yet (because I'm happy to give Parallax the opportunity to give direct debug tips if they would like)
• Poundy Posts: 15

  2012-09-11 02:40 edited 2012-09-11 02:40

  The very helpful folks at Parallax are sending out a replacement - awesome service folks !
• softcon Posts: 215

  2012-09-12 09:07 edited 2012-09-12 09:07

  I too am having trouble using the sp+/sp- for speaker output. When I plug in powered speakers, or earphones, it works just fine.
  However, using one of the button speakers from parallax, wiring sp+ and sp- to the matching pins on the button speaker only produces clicks, but no output of sound.
  I thought maybe this was a result of the basic stamp not having enough power left to power the speaker, but since it's powered by a 9-volt battery, this shouldn't be an issue.
  I do need to remove power from the emic2 while reprogramming the bs2, apparently the draw on the bs2 from the emic2 is too much to allow the programming to take place, but a simple unplugging of the 5V wire solves the problem.
  I'm not sure if the speaker pins (on the emic2) are incorrect or not, no way for me to tell, but if anyone else has tried this configuration (bs2/emic2/button speaker) and gotten it to work, I'd be interested in knowing how it worked out for you.
  If anyone has any suggestions on what I can try to make this work, I'd sure appreciate it, I was hoping to use the button speakers, to remove the need for earphone jacks being plugged and unplugged, but perhaps there's just not enough volume for the button speaker to pick up the output.
  I had my wife doublecheck the wiring for me before applying power (don't want to toast my shiny new emic2),, and (after changing locations of a couple of wires, off by one row) all was in order, but no sound out of the button speaker, but again, earphones/external speakers work just fine.
  Thanks for any suggestions.
• Poundy Posts: 15

  2012-09-12 15:39 edited 2012-09-12 15:39

  Hi Softcon,
  
  If you can get sound out of the socket, but not the SP+/SP- pins, then I actually suspect the speaker is the problem not the EMIC2. Do you have a 3.5mm plug you can solder the wires from the speaker onto, so you can eliminate the pins as the issue? Or an old set of headphones you can cut the wire on and splice&solder the speaker onto?
  
  The SP+/- wire polarity isn't super critical for a speaker to operate. It should still work if you have it reversed, although it likely won't be at an optimal volume. So there is little harm in reversing the connection from your speaker and seeing if that makes a difference to your experience.
  
  My last comment is that 9v batteies are really poor things to use, they don't have a very large current capacity which may be why you see issues, your battery may be sagging below a usable voltage during programming. I'd certainly try to eliminate that too.
• softcon Posts: 215

  2012-09-12 22:13 edited 2012-09-12 22:13

  I know the speaker works, because before rewiring the board to handle the emic2, I had it playing dec the halls (took it as a demo to show a friend when we went visiting last month) so speaker is good.
  Unfortunately, 9-volt battery is the only power I have to use other than the usb port on the board (it's a bs2 homework board usb version) If someone can suggest another way to give it more power, I'm all for trying it out, but afaik, there's nothing else I can feed power into the board with in it's current configuration.
  I of course do have a bs2 module (compliments of the mystery bag) so I could move the code to that, but I'm not yet sure how to wire that one up, since I've not delved into it's documentation to see which pins are what.
  On the other hand, I do have a quickstart board, but my understanding is that they provide even less power outputs on their vin connection, so I don't think that would help in this case.
  Any other suggestions will of course be greatfully accepted.
  I was kind of figuring the output power might be too low to drive the speaker in combination with the emic2, but here's a question.
  Can I move the power wire over to the vin port on the bs2, and obtain more power output that way? Would that help?
• Poundy Posts: 15

  2012-09-12 22:59 edited 2012-09-12 22:59

  I still think it's worth proving, if you can, that the speaker works on EMIC2 on the socket, since you know the socket works. I have been assuming that this is an 8ohm speaker - I can't find a Parallax speaker with "button" in it's name. Is this the speaker you're talking about? http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/speaker/List/0/SortField/4/ProductID/106/Default.aspx
  
  If so, that's a Piezo, not a "real" speaker so isn't going to work.
• softcon Posts: 215

  2012-09-13 04:29 edited 2012-09-13 04:29

  Ahh, got it. That is indeed the speaker in question. Good reason why it didn't work, sorry for the confusion. I'll find something else to use there. I did get a set of speakers fro the dollar store that are really cheap, cuting the cord, and stripping it and using that as a diect connection may work, I'll see what happens. Thanks for clearing that up for me, good reason why it was just clicking, expected behavior if it can't play those outputs.
• Poundy Posts: 15

  2012-09-13 13:18 edited 2012-09-13 13:18

  cutting the cord from the speaker wire should work fine ! Most speakers like that are 8ohm which will work fine. Good luck !
• Circuitsoft Posts: 1,166

  2012-09-13 15:02 edited 2012-09-13 15:02

  Publison wrote: »

  The Tip and Ring are connected together on the EMIC-2 board, so a mono plug should work just fine.

  No, no, no! Every mono plug I've seen shorts ring and sleeve together, so you must use a stereo plug.
• Poundy Posts: 15

  2012-10-09 22:20 edited 2012-10-09 22:20

  Parallax sent through a replacement for me - worked first time. Great support!
• Publison Posts: 12,366

  2012-10-10 12:04 edited 2012-10-10 12:04

  Circuitsoft wrote: »

  No, no, no! Every mono plug I've seen shorts ring and sleeve together, so you must use a stereo plug.

  
  Would't a short between Tip and Ring render the plug useless? I't only a two conductor plug.
• Circuitsoft Posts: 1,166

  2012-10-10 12:26 edited 2012-10-10 12:26

  Every mono plug I've seen, the ring and sleeve are the same contact, while Tip and Ring are generally Left and Right respectively.
  
  So, if the board you're plugging into (like this one) short Tip and Ring together to make stereo, then a mono plug (where ring and sleeve are the same) will short the output to ground.
• Poundy Posts: 15

  2012-10-11 21:01 edited 2012-10-11 21:01

  sigh - newbie problem here, anyone know how I trigger this to be "solved" now?
• RDL2004 Posts: 2,554

  2012-10-11 21:33 edited 2012-10-11 21:33

  Go to the first post in the thread, click "Edit Post", then "Go Advanced". On the next screen look for the drop down "pre-fix" menu thing and change to "Solved"
• Poundy Posts: 15

  2012-10-12 03:05 edited 2012-10-12 03:05

  Wow, ok, done. Weird place to do it, but I guess I get it... somehow, perhaps
  
  thanks everyone for the chat !