Shop OBEX P1 Docs P2 Docs Learn Events
How to revive SX28 — Parallax Forums

How to revive SX28

william chanwilliam chan Posts: 1,326
edited 2005-06-30 11:01 in General Discussion
How to revive a SX28DP that suddenly just died?
It stopped oscillations. ( it was programmed to use internal oscillator at 4Mhz )
It also refused to accept new downloads ( Chip Connection Error ) no matter how many times I try.
This SX was downloaded about 50 times in 1 week and it suddenly just died when I plugged in the SX-Key.

At first, I thought nothing about it, and just replaced the SX28 chip.
Then after about 1 week, the new chip also died in the same manner.

Usually I plug in the SX-Key with the chip still powered. Is this acceptable?

Could it something to do with the v3.10 IDE?

Comments

  • BeanBean Posts: 8,129
    edited 2005-06-29 10:58
    1) Make sure /MCLR is tied high.
    2) Make sure voltage is not too high or too low.
    3) Try removing resonator or anything connected to the OSC pins.
    4) Put a 0.01uF bypass cap as close to the SX chip as possible.
    5) I wouldn't recommend connecting the SX-Key with the power on (although I do it sometimes too).

    That's all I can think of right now. But I can tell you that I will re-program an SX chip hundreds of time in a week when I'm working on a new project.

    Bean.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "SX-Video·Module" Now available from Parallax for only $28.95

    http://www.parallax.com/detail.asp?product_id=30012

    Product web site: www.sxvm.com

    "What's the difference between ignorance and apathy ?"
    "I don't know, and I don't care."
    ·
  • william chanwilliam chan Posts: 1,326
    edited 2005-06-29 13:07
    Hi Bean,

    Thanks for your reply.
    But I don't think its to do with any of those that you listed, b'cos when I plug in a new SX28 chip, it just works.

    Anyway, are you the designer of the SX Video product?
  • BeanBean Posts: 8,129
    edited 2005-06-29 13:57
    Yes I designed the "SX-Video" module.
    And I have a SX-Video overlay module in the works...
    Bean.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "SX-Video·Module" Now available from Parallax for only $28.95

    http://www.parallax.com/detail.asp?product_id=30012

    Product web site: www.sxvm.com

    "What's the difference between ignorance and apathy ?"
    "I don't know, and I don't care."
    ·
  • william chanwilliam chan Posts: 1,326
    edited 2005-06-30 03:58
    What is an Overlay Module?
    For color display?
  • Paul BakerPaul Baker Posts: 6,351
    edited 2005-06-30 05:02
    Overlay superimposes images on an input video signal like some VCRs do when they say "REW" at the top of the screen while you are watching a TV show.
  • BeanBean Posts: 8,129
    edited 2005-06-30 11:01
    Paul is correct. It will receive serial text at 2400 baud and display it superimposed on an input video signal.

    It will display white text and dims the background where the text is to make it easier to see. There are 4 different text sizes that are software controlled (all text must be the same size) ranging from 1/4 of the screen (vertically) to full screen. You can also set what scan line you want the text to start on to position the text vertically on the screen.

    The prototype is working and the software is written, I'm working on a PCB layout now.

    If anyone want to make there own type of video overlay, I'm willing to assist. However right now, this project is not going to be "open-source".

    Bean.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "SX-Video·Module" Now available from Parallax for only $28.95

    http://www.parallax.com/detail.asp?product_id=30012

    Product web site: www.sxvm.com

    "What's the difference between ignorance and apathy ?"
    "I don't know, and I don't care."
    ·
Sign In or Register to comment.