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Any ideas for P2 demos?

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  • Cluso99Cluso99 Posts: 18,066
    One of the features of the P2 (P1 too) is the multi-core microcontroller. Now that PCs (ie Intel, and ARM too) have multiple cores, the P2 can be used to show how multiple cores can do separate things. This is not new, but another thing P2 can demonstrate without the GB baggage.

    As most of you know, I am all-in for a P2 OS and did that for P1.

    A minimum self-hosting P2 OS needs...
    * Serial (or USB port) and PC/Mac/RPi
    or
    * screen - Composite, VGA or HDMI
    * keyboard - PS2 or USB
    and
    * SD/microSD card
    plus
    * optional input/output port(s)
    such as...
    * LEDs
    * switches

    It is easy enough to build a board with these features :sunglasses:
  • cgraceycgracey Posts: 14,133
    Wuerfel_21 wrote: »
    The problem with something like the Pi is that it needs to run millions of lines of code you've never seen and probably don't want to see (and sometimes, are not allowed to see (GPU firmware, etc...) to do anything useful. P1 and P2 programming has small, highly optimized, self contained libraries that you can reasonably expect someone to read through, fully understand and modify. I think there is tremendous value in that.

    Me, too.
  • A Pi is really great value for money but I sometimes hate waiting for a Pi to boot up when you fire it up and it has no decent low power/sleep modes it can wake from. A P2 could boot in a second or so like some of the original machines we used to use back in the day when we had it good.

    Something hangs in your code just press reset and it is back up again. :smile:
  • rogloh wrote: »
    A Pi is really great value for money but I sometimes hate waiting for a Pi to boot up when you fire it up and it has no decent low power/sleep modes it can wake from. A P2 could boot in a second or so like some of the original machines we used to use back in the day when we had it good.

    Something hangs in your code just press reset and it is back up again. :smile:
    No problem. C64's are readily available on eBay. You don't need the P2 to regain that world! :smile:

  • LOL.
  • You can get a Pi to boot within a few seconds with a custom (or seriously butchered) Linux distro. I started writing a fake init a few years ago that would first spawn the main application and then re-exec itself to run the real init; that way, the main application would start right away, while the rest of the system (which wasn't really necessary) could take its good old time starting up. There was the caveat that the main application had to understand that most other things (such as a writable filesystem) wouldn't be ready for a while, but it could nevertheless start the GUI right away. There's some way to have the Pi render directly into a Linux framebuffer using OpenGL, so I didn't have to bother with an X11 server or anything.

    Fortunately, before I got it working well, the project requirements changed, and I was able to use a Propeller with buttons and an LCD instead of a graphical touchscreen.
  • pqwepqwe Posts: 1
    edited 2020-04-24 20:30
    Have you considered releasing a Robot to go along with the launch of the Prop 2? I was thinking about something along the lines of the Stringray? I always was a fan of the robot and the platform :smile: I know the board that went along with it was controversy but I did like the functionality and convenient on-board motor controller. Or was that robot not considered a success?
  • I think what needs to be sold is flexibility, not talent at performing a certain task:

    "The P2 can do this." "Yes, but a RasPi can do it better and cheaper."
    "The P2 can do that." "Yes, but a DSP chip can do it better and cheaper."
    "The P2 can do another thing." "Yes, but a you-name-it chip can do it better and cheaper."

    The P2's selling point has to be that it can do this, that, and the other thing, simultaneously, in separate processors. It's all about functional integration, not narrow ability in one realm or another, where it will always be beaten.

    -Phil
  • I think what needs to be sold is flexibility, not talent at performing a certain task:

    "The P2 can do this." "Yes, but a RasPi can do it better and cheaper."
    "The P2 can do that." "Yes, but a DSP chip can do it better and cheaper."
    "The P2 can do another thing." "Yes, but a you-name-it chip can do it better and cheaper."

    The P2's selling point has to be that it can do this, that, and the other thing, simultaneously, in separate processors. It's all about functional integration, not narrow ability in one realm or another, where it will always be beaten.

    -Phil

    +1
  • cgraceycgracey Posts: 14,133
    I agree, Phil. That's what we need to do.
  • RaymanRayman Posts: 13,797
    I've described p1 as Swiss army knife and I think even more so for p2...
  • Something like the evaluation board with the plugin modules supported by the right software could be useful to show the dynamic design possibilities.
    The modules would need to be hot-swappable by design.

    Maybe you have VGA video connected on a set of pins. You change one setting (say, by pressing a button or editing a text field) and unplug the VGA connection, then plug the HDMI connection into the same pins on the chip and there is your display still operating. Another setting change and you plug the VGA connection into a new set of pins and extend the display.
    You exhaust the current set of control buttons, so plug in some more. You find a keyboard interface more useful, so you swap to that on the same pins and load a different software control module. Switch from analogue audio to I2S on the same pins. These sorts of changes to the design on other platforms requires quite a bit of rework.
    This would be more attractive to product developers than product users.
  • RaymanRayman Posts: 13,797
    edited 2020-04-25 01:00
    I'm thinking VGA is way better than HDMI for P2... (for monitors, maybe not for LCD).
    You get 1080p with less pins...

    I looked on Amazon today and a cheap "choice" still has VGA input. I'm thinking we have a few more years where VGA input for monitors is normal...

    TVs are starting to not have VGA, but there are cheap adapters...
  • Roy ElthamRoy Eltham Posts: 2,996
    edited 2020-04-25 01:52
    PhiPi is right once again.

    Rayman,
    I think component (not composite) is probably better than VGA if you are foregoing HDMI.

  • evanhevanh Posts: 15,126
    If there is another board designed I'd be wanting a HyperRAM chip on board as an integral component for top performance. This means those I/O pins can't have tracks out to an expansion connector. Or at least you'd have to move a set of jumpers over to the alternative route if not wanting to use the HR.

  • evanhevanh Posts: 15,126
    Roy Eltham wrote: »
    I think component (not composite) is probably better than VGA if you are foregoing HDMI.
    Component video support seems to have a very fussy heritage. In theory it's as good as VGA but TVs treat it as only a DVD source and monitors don't support it at all. The supported video modes shrinks a lot.

  • Cluso99Cluso99 Posts: 18,066
    edited 2020-04-25 05:29
    I think what needs to be sold is flexibility, not talent at performing a certain task:

    "The P2 can do this." "Yes, but a RasPi can do it better and cheaper."
    "The P2 can do that." "Yes, but a DSP chip can do it better and cheaper."
    "The P2 can do another thing." "Yes, but a you-name-it chip can do it better and cheaper."

    The P2's selling point has to be that it can do this, that, and the other thing, simultaneously, in separate processors. It's all about functional integration, not narrow ability in one realm or another, where it will always be beaten.

    -Phil

    +1

    Unfortunately, P2 is no longer the simple microcontroller that P1 was. Where it was easy to learn the P1, P2 is quite complex.
    There needs to be some simple description to get one going, without delving into all the complexities. I never got into the ARM family because of the ~400++ page manual. Unfortunately P2 has to be headed there too :(

    I think we definitely need an OBEX. But I'm sorry, IMHO git is not the solution IMHO.
  • Cluso99Cluso99 Posts: 18,066
    edited 2020-04-25 05:37
    Roy Eltham wrote: »
    PhiPi is right once again.

    Rayman,
    I think component (not composite) is probably better than VGA if you are foregoing HDMI.
    Actually, I disagree (component v VGA) Roy.

    I have 5 x 24" monitors in our household atm. All have VGA. Some have HDMI too, some have DVI, and some have all 3. None have component, none have composite. Smaller VGA monitors are even being chucked out on scrap heaps.

    The only bad thing about VGA is the connector size.

  • Cluso wrote:
    I think we definitely need an OBEX. But I'm sorry, IMHO git is not the solution IMHO.
    Sadly, I have to agree. Git is like a Swiss Army knife. As soon as you've figured out one blade, another stabs you in the back. I've been trying to navigate github with respect to my Blockly adventures. But, honestly, everything I do is by rote. Nothing makes sense to me at a gut level. I can't imagine what a newbie must be experiencing who just wants to take advantage of someone else's Spin or C code. It's the wrong platform for Parallax to be using as an OBEX replacement, and I hope they come up with something better soon.

    -Phil
  • I understand and use git (mainly github) quite a lot, and I agree it's not a good OBEX substitute.

    The main issue for me is that it's painful to just get the one or two things you want. It's trivial to get the whole thing, but getting a single source file requires navigating to the file and then viewing it raw and saving it manually.
    There's probably a command line way to grab just the one or few files you want, but it's going to be something non-obvious and still require setup commands to connect to the repo and whatnot.

    RE: Component vs VGA, I wasn't saying it was better at being available, but better quality for usually less pins. But really, I prefer HDMI, everything I own that can display video has an HDMI input.
  • Cluso99Cluso99 Posts: 18,066
    edited 2020-04-25 08:48
    VGA v HDMI
    Certainly the HDMI connector is nicer than the VGA.
    I know there are cheap HDMI to VGA converters. Just not sure what the cheap passive ones do? Do they take VGA from a different set of HDMI pins or what? I haven’t spent the time researching this.
    Does anyone know what would be required to put an HDMI socket on a P2 board that would allow HDMI or VGA (using a cheapie VGA converter) and what are the code differences required?
  • If you use an HDMI connector, all 8 P2 pins go to it. So adapting to VGA is a matter of taking 5 of those 8 pins (and ground) to the vga cable. Jaycar sell the plugs so you can solder yourself.

    The code difference... just use Roger's driver that drives 5 main types of video. HDMI has limited resolution due to the need for such a high serialised bit rate, but VGA can happily do 1080p

    Also, by using the resistor output modes, and ADC bitstream input, we can detect what pins have 75 loads on them, to somewhat autodetect the base pin address and type of monitor connected. OzPropDev wrote some demo code for this.

  • evanhevanh Posts: 15,126
    Roy Eltham wrote: »
    RE: Component vs VGA, I wasn't saying it was better at being available, but better quality for usually less pins. But really, I prefer HDMI, everything I own that can display video has an HDMI input.
    Ah, it would be interesting to compare VGA-to-HDMI vs Component-to-HDMI converters.

  • Roy Eltham wrote: »
    I understand and use git (mainly github) quite a lot, and I agree it's not a good OBEX substitute.

    I suggest to continue the discussion about OBEX and GITHUB here.

  • Component can do 1080p on most modern TVs. It's not spec'd and some TVs will only do 1080i on them, but I believe Chip did 1080p on component a while ago and I know 2 of my displays with component in can do it.

    Cluso99,
    I have no idea how a "passive" converter from HDMI to VGA would work, there's no VGA compatible signals on any of the HDMI pinouts that I have seen. I've only ever seen "active" boxes for converting HDMI to VGA or vice versa.
    DVI-I connections do have the analog VGA compatible pins, DVI-D does not. DVI-A is analog only for video signals, the TDMS pins are missing. You can go from DVI-I to both HDMI and VGA with simple passive adapters, perhaps that is what you are thinking of?
  • Cluso99Cluso99 Posts: 18,066
    Thanks Roy.
    I thought the cheapie HDMI to VGA boxes and cables were just passive, but looking a little closer it seems they use an NXP chip.
    I do have a dongle that converts DVI to HDMI. Not sure which way, if it matters.
    I need to do more research, but not today.
  • Not to hijack this thread but on the video discussion. What would be a good LCD for the P2 eval b board. Something in 3.5 to 5 inch display. Software also.

    Thanks in advance.
  • evanhevanh Posts: 15,126
    Cluso99 wrote: »
    I do have a dongle that converts DVI to HDMI. Not sure which way, if it matters.
    That one is passive because it's digital to digital. HDMI standard was piggybacked on existing DVI.

  • RaymanRayman Posts: 13,797
    Newhaven has good lcds on digikey. There are also hdmi and eve2 versions for not much more
  • Would it be possible to consolidate the ideas somewhere? Or has that already been done and I've missed it?
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