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Propeller 2 Live Forum - Open learning and support (topics, speakers and registration!) - Page 12 — Parallax Forums

Propeller 2 Live Forum - Open learning and support (topics, speakers and registration!)

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  • hinvhinv Posts: 1,252
    edited 2020-12-29 14:50
    @"Ken Gracey" What is the difference between the different videos listed for the 22nd?



    vs.




    P.S. The beard looks good on you.
  • cgraceycgracey Posts: 14,131
    Hinv, each ADC has its own unique offset that can be nulled via a first-order equation using calibration readings from GND and VIO. That is why traces weren't stacking directly on top of one another. Not sure about the red line at 1:30. Maybe I had also connected it to the function generator? At one point, I was feeding the function generator into two pins, but due to their offset, they were separated vertically by a small amount.

    All our boards have 20MHz crystals on them. Asking for 333_333_333 Hz actually gets you that frequency, not accounting for crystal inaccuracy. We can divide the crystal frequency by 1..64, then multiply it up by 1..1024.

    In the future, I will probably use serial more efficiently, getting away from text. For now, you can see all transmissions in text in the main DEBUG window, which makes it easy to work with.
  • cgraceycgracey Posts: 14,131
    Hinv, I just realized that the red line was pin 9, which has a timing problem at very high frequency. I was overclocking to 333MHz and on both my boards, pin 9 exhibited ADC noise, which is most likely a setup-time or hold-time issue. Backing down to 320MHz made it go away.
  • Chip's DAC video from this afternoon is now posted on YouTube! See the fist post above for the link.

    Ken Gracey
  • JRetSapDoogJRetSapDoog Posts: 954
    edited 2020-12-30 17:30
    The following quotes pertain to the A2D video on December 22nd:
    hinv wrote: »
    What is the red line doing at about 1:30:00? It is obvious that your signal generator is tied to the green and yellow line, and blue looks like it is floating at midpoint. If red is floating, why is it so much lower?
    cgracey wrote: »
    Hinv, I just realized that the red line was pin 9, which has a timing problem at very high frequency. I was overclocking to 333MHz and on both my boards, pin 9 exhibited ADC noise, which is most likely a setup-time or hold-time issue. Backing down to 320MHz made it go away.
    Somewhat similarly, for the D2A video on December 29th, I was wondering why the rising part of the red sawtooth trace at 0:42:00 (which uses decimal offsets) doesn't appear to be as centered between the green and blue traces as it does at 0:41:30 (which uses hexadecimal offsets). The former scope view is after Chip changed the offset values to decimal values (specifically 10, 20, 30 and 40) in response to Ken's question. Initially, I wondered if the apparent non-centeredness had something to do with the decimal numbers not being powers of two. Or maybe it's related to the pin 9 thing. Or maybe my eyes are just not resolving things well. Or maybe the darkness of the red pixels results in some kind of shift. Anyway, I'm still working my way through the video (took a break after watching half). Thanks for the excellent A2D and D2A presentations Chip & Ken.
  • PublisonPublison Posts: 12,366
    edited 2021-01-03 16:52
    Ken Gracey wrote: »
    Chip's DAC video from this afternoon is now posted on YouTube! See the fist post above for the link.

    Ken Gracey

    Hey Ken. When will the video

    Propeller 2 Live Forum: JonnnyMac Holiday Bundle Part 2

    be available?

    I was in a doctor's office during the whole presentation. :(
  • Doh! Forgot to check the YouTube channel. Thanks!
  • Personally I've since long ago subscribed to Parallax YouTube channel and thus get a notification of new videos uploaded. Thus I become aware of the above video right away and watched it a bit later, mostly at 1.4x speed :blush: to save time.
  • Yes, we're getting them posted within 48 hours. The fastest way to know about the notifications is to subscribe to our YouTube channel, like @banjo pointed out.

    Once we are done with a P2 Live Forum, the Zoom file must be converted (1-2 hours). Then it is uploaded to YouTube (30 mins - 2 hrs). It's difficult to get this done the day of the event because it's already late in the day.

    But we're speeding it up a bit.

    Ken Gracey
  • Bryan and I have successfully timestamped Ray's presentation from last year :smile:

    https://youtu.be/wmzQY6SayQE <- click "show more" where the description is to see the list.

    30 more to go!

    Ken Gracey
  • Hey all,

    This week we have JonnyMac's beginner series on Wednesday at 4:00 pm Pacific.

    Also, I will quickly schedule a P2 Live Forum for Tuesday at 3:00 pm Pacific. We'll have a guest presenter, Kevin. I just gave him a call to hear about what he's doing with the P2 and he'd like to share his project with the group tomorrow. Aside from him, we'll be open forum - whatever is of interest to people.

    Expect to see an invitation link this evening.

    Ken Gracey
  • Ken GraceyKen Gracey Posts: 7,386
    edited 2021-01-05 02:21
    Hey all,

    I've updated the first post with registration links.

    We have a P2 Live Forum tomorrow at 3 pm Pacific, and one at 4:00 pm Pacific on Wednesday.

    Ken Gracey
  • I'll be showing up for the first time assuming I'm registered (Not the faintest clue how Zoom works)
    Should be fun, can't wait to talk with everyone.
  • Hello P2 fans!

    I've made changes to the first post in this thread too numerous to list!

    Two P2 Live Forum registration links posted this week - open discussion on Tuesday and JonnyMac on Wednesday.

    Three video links added for prior P2 Live Forums.

    See ya this week!

    Ken Gracey
  • moony wrote: »
    I'll be showing up for the first time assuming I'm registered (Not the faintest clue how Zoom works)
    Should be fun, can't wait to talk with everyone.

    We welcome you @moony to the P2 Live Forum. Pleased to have new people and we'll be happy to catch you up with the rest of the community if you're feeling like a lost bit.

    Ken Gracey
  • Hello!

    Registration link for Tuesday's P2 Live Forum: Space Invaders with Jim Bagley now added to first post!

    Registration link for Wednesday, January 27th with Jonny Mac + SPI Interfacing is also added to first post.

    Ken Gracey
  • Was Baggers zoom session recorded?
  • Hi

    I got this e-mail last week- that's the latest as far as I know
    The meeting below has been canceled.
    Topic: P2 Live Forum: Space Invaders with Jim Bagley
    Time: Jan 18, 2021 02:00 PM Pacific Time (US and Canada)
    Meeting ID: 885 0305 9920

    The host has sent you a message:
    Whoops! Used the wrong date! Expect another e-mail from me. Ken
    If you have any question, please contact the host at kgracey@parallax.com.

    Dave

  • There was a meeting with Jim Bagley (last Tuesday). Since Ken was the meeting host, I'm fairly certain it got recorded.
  • Greetings!


    First post updated with this Tuesday and Wednesday's P2 Live Forum and the link to Jim Bagley's Space Invaders from last week!

    Ken Gracey

  • On Tuesday's P2 Live Forum we have some important topics to discuss relative to a new board: P2-EC HyperRAM.

    I'll also share the roadmap in a long-delayed answer to @Mike Green's question "Ken, where do we find objects on your web site?" about two months ago. The answer is a work in progress, seeking community feedback.

    Ken Gracey

  • tritoniumtritonium Posts: 539
    edited 2021-02-02 10:29

    Hi
    @Ken Gracey
    Haven't seen any announcements about Zoom meetings tonight or tomorrow- have I somehow missed them?
    Dave

  • There's a meeting today at 2:00 pm. I am now posting the registration links here https://www.parallax.com/events/ because I don't have the time to maintain two locations. I will amend the first post in this thread so people are aware of where to find the registration links.

    Thanks,
    Ken Gracey

  • cgraceycgracey Posts: 14,131

    Sorry, Guys. Our power went out and, of course, Zoom quit working. Hopefully, you all were able to stay on and keep talking.

  • cgraceycgracey Posts: 14,131
    edited 2021-02-03 02:21

    The same power pole hit two weeks in a row. Gas, liquor, EBT, deli, boat, BOOM!!! I never realized the power pole was right outside the front door.


  • @cgracey said:
    The same power pole hit two weeks in a row. Gas, liquor, EBT, deli, boat, BOOM!!! I never realized the power pole was right outside the front door.

    Sounds/Looks like they should either move the pole or surround it with a bunch of steel bumpers to keep it from getting hit...

  • Cluso99Cluso99 Posts: 18,066

    That's what happens when driving your boat up the main street ;)

  • rajputaman04rajputaman04 Posts: 1
    edited 2021-02-16 15:30

    I would like to present but don't know the best time. Should there be a standardised/recommended best time/place? mx player for pc

  • cgraceycgracey Posts: 14,131

    @rajputaman04 said:
    I would like to present but don't know the best time. Should there be a standardised/recommended best time/place?

    You can next Tuesday. When the Zoom meeting starts, just type into the chat box that you have something to present.

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