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Propeller Platform or Protoplus Module issue?? — Parallax Forums

Propeller Platform or Protoplus Module issue??

tdg8934tdg8934 Posts: 126
edited 2012-02-11 22:42 in Propeller 1
I received my Propeller Platform and Protoplus Module yesterday. I think I am stil having issues with the Propeller Platform or ProtoPlus board.

I am able to run the example Blinky LED type examples and see the LED blinking at various rates when the program is modified.

However, I soldered up the ProtoPlus board and verified all connections with a continuity meter and all is good. Im an Electrical Engineer and have been soldering for 35+ years so I know everything is good. I makes me believe something is wrong with the Propeller Platform but then why is the Blinky LED programs running fine.

Is there any other way, I can troubleshoot this (besides flashing a LED off/on at different rates)?

The only other thing I have tried to do is F10/F11 the various Graphics, Audio, TV related Demo's to have them seen by my TV video/audio inputs. I get nothing but the blue screen on my TV when I run any video or audio demo program. I even tried the PBASIC programs and nothing. I know my TV inputs work because I normally use it for my XBOX 360 which works great (Yellow - video, Red/White - audio). I have tried different audio/video cables too.

This is very trivial stuff to me to troubleshoot this but I'm running out of ideas on what to do next.

Comments

  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-02-11 10:37
    Here's the checklist I can think of:

    Hardware:
    • Does the TV work with something else plugged in?
    • Is the cable between the TV and the Protoplus working?
    • Are the pins 12,13,14 on the Propeller Platform capable of flashing an LED?
    • Are the pins 12,13,14 on the top of the Protoplus board capable of flashing an LED?
    • Has the crystal been swapped on the Propeller Platform with a different value? Is it socketed well?


    Software:
    • Start with the standard "Graphics Demo" using the Propeller Tool.

    Generally, things like having the resistors in wrong will result in an image that doesn't look right, but is discernible from nothing at all.

    Update us! Please.

    OBC
  • tdg8934tdg8934 Posts: 126
    edited 2012-02-11 11:16
    Jeff,

    •Does the TV work with something else plugged in?
    Yes, my XBOX 360 works well on the TV video/audio inputs

    •Is the cable between the TV and the Protoplus working?
    I tried 2 different cables and nothing with either.

    •Are the pins 12,13,14 on the Propeller Platform capable of flashing an LED?
    I tried the Blinking LED spin tests on P0, P1, P11, P12, P13, P14 and it does blink off/on the same as it should.

    •Are the pins 12,13,14 on the top of the Protoplus board capable of flashing an LED?
    I tried the Blinking LED spin tests on P0, P1, P11, P12, P13, P14 (on top in the holes) and it does blink off/on the same as it should.

    •Has the crystal been swapped on the Propeller Platform with a different value? Is it socketed well?
    The crystal is pushed in but has a slight bit of play moving it top of the board to the bottom. Overall, I beleive it is good as the blinky LED tests change rates when delays are entered into the code.



    •Start with the standard "Graphics Demo" using the Propeller Tool.
    Also did F10/F11 with Graphics_Demo.SPIN and still nothing on my TV

    Generally, things like having the resistors in wrong will result in an image that doesn't look right, but is discernible from nothing at all.
    I checked all the resistor values with my meter and everything is good as it should be.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-02-11 11:37
    Wow..

    Ok.. Next step.. Does your Protoplus board have Pw and Px indications on a couple of the traces? This is a new board design. I need to know if you have the older revision or the new unit.

    I just checked the shipping logs, so I know which board you have. I've sent a message to Nick so that we can get this squared away quickly.

    Jeff/OBC
  • pedwardpedward Posts: 1,642
    edited 2012-02-11 11:58
    Have you done end-to-end connectivity tests from the RCA jack to the propeller? You should be able to ohm out the 4 connections back to the prop.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2012-02-11 12:08
    tdg8934 wrote: »
    I checked all the resistor values with my meter and everything is good as it should be.

    How about checking the resistance from the RCA connector to each of the Propeller's video pins (P12-P14 IIRC)? Just to make sure all the connections are good all the way to the chip.

    I'd also suggest using a program that outputs to a terminal window at a relatively high baud rate to make sure the crystal PLL circuit is okay.

    Edit: I see pedward had the same idea.
  • tdg8934tdg8934 Posts: 126
    edited 2012-02-11 13:30
    Thanks to all for your help!


    I did a continuity/ohm check from the Propeller Platform propeller pins (P12,13,14) to the header pins to the ProtoPlus header pins to the resistors to the video RCA jack and all checks out good. I also did the same for P11 to the 47uF cap (+) on the ProtoPlus (which goes to the audio RCA jack) with all checking out good.

    As far as the Parallax Serial Terminal goes, when I run the Parallax Serial Terminal Demo.SPIN program, I originally saw a garbled character come out but thats it (when I click on the Enable button). If I type something in, it echoes back correctly (in English (not garbled)).

    Running it again....I see the messages come up correctly on the Parllax Serial Termnial Demo program.


    Parallax Serial Terminal Demonstration

    *** Number Feedback Example ***


    Enter a decimal value:

    Could something be wrong with the Propeller Platform?

    What else is left?
  • Duane DegnDuane Degn Posts: 10,588
    edited 2012-02-11 13:45
    Do you have a different TV you could try?

    I haven't found any TVs that don't work with the Prop but one of my VGA monitors doesn't like the Prop's VGA signal.

    I thought I read something about the Prop's composite signal not being completely up to specs. Maybe your monitor doen't like the Prop's signal.
  • AribaAriba Posts: 2,690
    edited 2012-02-11 13:58
    What voltage do you measure at the Video output on the Protoplus with and without the TV connected?

    With the Graphics demo I measure ~0.96V without, and 0.29V with the TV connected.

    Andy
  • pedwardpedward Posts: 1,642
    edited 2012-02-11 14:02
    Dumb question, but have you tried swapping cables? The video output is baseband composite with separate audio unless you enabled broadcast video. The video is present on the connector with 3 resistors and audio on the other connector.

    Also, have you checked that the demo you are running has a Start(12), to indicate pin 12 as the base output pin for video?
  • tdg8934tdg8934 Posts: 126
    edited 2012-02-11 14:06
    Well good news (sort of). My 32" Vizio Plasma TV video inputs does not recognize the ProtoPlus video/audio jacks. However, my daughters 32" Vizeo LCD (a little newer) TV video inputs DOES recognize the ProtoPlus video/audio jacks. So on her TV I could see the Graphics Demo running (Pretty neat looking). But my living room 32" Vizio Plasma TV does not work (but it does for my XBOX 360 and BlueRay player). Hmm.

    Guess I need to get a small LCD screen to view the ProtoPlus on.

    http://www.parallax.com/Store/Accessories/Displays/tabid/159/CategoryID/34/List/0/SortField/0/Level/a/ProductID/336/Default.aspx (but the ProtoPlus doesn't have PS2 connectors for the Mouse and Keypad).

    http://www.parallax.com/Store/Accessories/Displays/tabid/159/CategoryID/34/List/0/SortField/0/Level/a/ProductID/337/Default.aspx

    Becoming expensive now...

    Does these conclusions sound right?
  • Cluso99Cluso99 Posts: 18,069
    edited 2012-02-11 14:13
    tdg8934: Firstly welcome to the prop forum.

    What you seem to have found is some form of incompatibility. Do you by chance have your TV set to PAL rather than NTSC (which is the default on most of the TV demos)? BTW I dont know what the XBOX etc output). This is just a guess.

    Now, if that does not work, you can try a 191R resistor across the TV Video output and ground. Phil calculated that the 75ohm termination is not actually correct with just the 3 series resistors, and we have since taken account of the props internal ~27ohm impedance too, which means 191R is not quite correct.

    Normally, we just compile and everything works fine. Something is not right with your setup, but its not a common problem. And the circuit is quite simple. So keep trying!

    Postedit: If you dont have 191R, try the a higher value.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-02-11 14:38
    A thought..

    This would be the first time I'd ever heard of an NTSC TV not work with the standard Propeller video DAC, but...
    I HAVE seen TV's which which not display a video signal if they did not detect an audio signal and vis-versa.

    You might try this demo..
    wip_nyan.zip

    OBC
    zip
    zip
    wip_nyan.zip
    21K
  • tdg8934tdg8934 Posts: 126
    edited 2012-02-11 14:41
    I went to grab a 220 ohm resistor and before I did anything with it, I plugged the video and audio cables back into my ProtoPlus and TV A/V jacks. This time everything WORKED and the demo was running on my living room Vizio 32" Plasma TV.

    I don't understand these intermittent issues of not working and not all of a sudden working. It makes me want to think poor soldering connections but everything is good visually. Also one might think the cables were not plugged in tight but they always were and I tried 2 sets of cables too.

    All is working now which is a good relieve.

    Now I'm justing waiting on my Adafruit 32x16 RGB display to come in the mail which Rayman has written Propeller drivers for it - to try out this week.

    Thanks to all for the great support.
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2012-02-11 14:49
    Woot!

    Video/Audio! Two of the coolest things on the Propeller!

    Jeff/OBC
  • tdg8934tdg8934 Posts: 126
    edited 2012-02-11 15:13
    Jeff,

    One other oddity that you mentioned
    I HAVE seen TV's which which not display a video signal if they did not detect an audio signal and vis-versa.

    On both my Vizio Plasma TV and my daughters Vizio LCD TV, you will not hear audio (ie. WavPlay.pbas) unless some video signal is present on the TV video yellow jack. On her tv, I sent video from her BlueRay player (audio from the Prop) and my tv, I sent video from my XBOX (composite yellow video jack) with audio from the prop. No audio is heard on the TV unless video is driving the TV video jack. As a test to see if it was prop related or just my TV related, I connected only the white and red audio jacks from the XBOX 360 to the tv with no video from the xbox. Nothing was heard on the TV until I plugged back in the XBOX video cable into the TV video jack again. Wow. Not that pratical for Vizio.
  • cavelambcavelamb Posts: 720
    edited 2012-02-11 15:42
    tdg8934 wrote: »
    I went to grab a 220 ohm resistor and before I did anything with it, I plugged the video and audio cables back into my ProtoPlus and TV A/V jacks. This time everything WORKED and the demo was running on my living room Vizio 32" Plasma TV.

    I don't understand these intermittent issues of not working and not all of a sudden working. It makes me want to think poor soldering connections but everything is good visually. Also one might think the cables were not plugged in tight but they always were and I tried 2 sets of cables too.

    All is working now which is a good relieve.

    Now I'm justing waiting on my Adafruit 32x16 RGB display to come in the mail which Rayman has written Propeller drivers for it - to try out this week.

    Thanks to all for the great support.

    Sounds suspiciously like cables, or loose connections.
    But glad to hear you got it running.
  • Cluso99Cluso99 Posts: 18,069
    edited 2012-02-11 22:42
    Glad you are up and running, and thanks for letting us know.
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