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Propeller II: Emulation of the P2 on FPGA boards (Prop123-A7/A9, DE0-NANO, DE2-115, etc) - Page 23 — Parallax Forums

Propeller II: Emulation of the P2 on FPGA boards (Prop123-A7/A9, DE0-NANO, DE2-115, etc)

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  • jmgjmg Posts: 15,171
    evanh wrote: »
    It was statements like that that solidly put Billy in the dunce bin early on. It told me he didn't code and was just another mumbo jumbo marketer.
    Problem is, Billy did not say that- quite the opposite. He managed to push up the memory, by lobbying the hardware designers.
    The hardware was not Microsoft's domain, and IBM of course, wanted lowest costs.
    Who knows if there was also some 'turf protection' in there too, seems quite likely.

  • evanhevanh Posts: 15,848
    Presumably it wasn't said by anyone at all then.

    Just some belated joke inserted some years later. I didn't here of it myself until the 1990's.
  • evanhevanh Posts: 15,848
    One detail is the original PC only came with 64 kB and maximum was 256 kB. Even the XT only had 256 kB. It wasn't until the clones started arriving that people started seeing more than that.

    Any limit clearly wasn't reached early on.

    For RAM chips it's adding notable extra cost burden to go beyond 512 kB for very little extra benefit. I'd side with IBM on that one.

    The real problem was the tiny 1 MB segmented virtual address range of the 8086.
  • TorTor Posts: 2,010
    evanh wrote: »
    One detail is the original PC only came with 64 kB and maximum was 256 kB.
    The first, low-cost model actually had only 16KB, and could be upgraded to 64KB. The next revision of the motherboard could go to 256KB.
    My desktop computer has a million times more memory, and it's way too little.

  • kwinnkwinn Posts: 8,697
    Tor wrote: »
    .......

    My desktop computer has a million times more memory, and it's way too little.

    It's the software version of having things accumulate to fill all available space.

    Spend time cleaning up, adding shelves, organizing stuff, and disposing of unwanted stuff to make room, and a short time later it's time to do it again.
  • TorTor Posts: 2,010
    Ah.. entropy. The second you stop pouring energy into reducing entropy it starts increasing again. The heat death of us all.
  • kwinnkwinn Posts: 8,697
    Tor wrote: »
    Ah.. entropy. The second you stop pouring energy into reducing entropy it starts increasing again. The heat death of us all.

    Hmm. Never thought of it as entropy but that's a pretty good analogy.
  • Heater.Heater. Posts: 21,230
    Hmm...technically if you are pouring energy into something you are increasing it's entropy.

    δS = δQ/T

    Where δS is the change in entropy and δQ is the change in energy. T is the absolute temperature.

    Or for a black hole, like a teenagers bedroom...

    S = kA / 4(l^2)

    Where k is Boltzmann's constant, A is the area of the event horizon and l is the Panck length.


  • TorTor Posts: 2,010
    Well, if you just pour energy into it randomly.. then entropy increases. But you can use energy to do work, and that work can be to clean up a room. Local entropy decreases. After you stop spending energy, it immediately starts geting dusty, messy, and unordered. Entropy increases.
  • kwinnkwinn Posts: 8,697
    Heater. wrote: »
    Hmm...technically if you are pouring energy into something you are increasing it's entropy.

    All depends on your point of view. If space to store stuff is what you are measuring instead of energy then more stuff means less space so entropy increases.
  • Where can I purchase a Prop123-A9 or BeMicro-A9 as I really need to get some coding done ready for the release of P2.

    On that note, is there any idea when P2 will be available and in want variants/prices?

    Rob
  • cgraceycgracey Posts: 14,134
    Where can I purchase a Prop123-A9 or BeMicro-A9 as I really need to get some coding done ready for the release of P2.

    On that note, is there any idea when P2 will be available and in want variants/prices?

    Rob

    Parallax has some Prop123-A9 boards in stock. I believe they are $475. Not sure about the BeMicro-A9 availability, though we've been supporting it with FPGA releases.

    About the Prop2 availability, I'm not sure. We are getting close, though. I imagine we'll sell it for around $8 in low volume, maybe less. We don't know exactly what our costs will be, but it's a big die at 8.5 x 8.5 mm and it goes into an exposed-pad TQFP-100 14 x 14 mm package.
  • SeairthSeairth Posts: 2,474
    edited 2017-04-05 15:09
    Where can I purchase a Prop123-A9 or BeMicro-A9 as I really need to get some coding done ready for the release of P2.

    On that note, is there any idea when P2 will be available and in want variants/prices?

    Rob

    For your first question, contact Parallax Sales for the Prop 1-2-3 board. I don't know if the BeMicro CV A9 is available for purchase anymore.

    For your second question, the answer is simply "no". Meaningful answers to availability, price, and variations have not been given yet. If you still want non-meaningful answers, they would be "soon", "reasonable", and "full capabilities first, then smaller variants at a later time".

    (edit: or what Chip said. :D )
  • For 'BeMicro CV A9' look here:
    http://forums.parallax.com/discussion/165978/2x-bemicrocv-a9-as-new-in-box-for-sale

    I know that one of these is gone ;-)
    Maybe the second is available, yet.
  • Thanks for the quick answers

    Rob
  • Apologies if it's already been asked (this is such a huge thread), what is the counter resolution on the P2?

    Thanks

    Rob
  • Apologies if it's already been asked (this is such a huge thread), what is the counter resolution on the P2?

    Each pin can be configured as a 32-bit counter that can, depending on mode, increment every clock cycle. I suggest reading about the smart pins in the documentation. You can find that link at the top of this post:

    http://forums.parallax.com/discussion/162298/x/p1
  • evanhevanh Posts: 15,848
    edited 2017-04-06 13:16
    Here's the Smartpins section of the Prop2Doc: (EDIT: You'll see references to a 32 bit Z register. This is a special register in each smartpin. Depending on how the smartpin is configured, that Z holds such values as a counter total or time totaliser or pulse length of the last input at that smartpin.)
  • Thanks. I thought that was the case making a resolution of 5nS for a 200MHz system clock.

    Rob
  • evanhevanh Posts: 15,848
    Yep. :) Note, that's expected to be overclocked at 200 MHz though.
  • Overclocked? What is the expected/recommended system clock?
  • jmgjmg Posts: 15,171
    Overclocked? What is the expected/recommended system clock?
    FPGA builds are all at 80MHz, and the target for silicon is 160MHz, but that may be a 'fingers crossed' number.
    Real layout simulations should give some idea, when those are reached.

  • evanhevanh Posts: 15,848
    It might work out better but Chip certainly hasn't promised any better than 160 MHz. As JMG says, nailing down some hard numbers is still to come.

    That said, I got the impression Chip is expecting 160 MHz to be an easy target after the struggles of the earlier Prop2-Hot design effort. He has said a few times of the conscious redesign steps made to eliminate poor critical path times.
  • evanhevanh Posts: 15,848
    I've been fishing around to verify what the finished IC packages might be. Thermal pad is a fixed parameter for all.

    There's an old statement that still seems to be accurate - https://www.parallax.com/news/2014-09-19/propeller-2-schedule-update-longer-we-work-simpler-our-new-multicore-design-will

    The titbit there is "64 I/Os in thermal-pad 100-pin TQFP package"

    Then, less than a year ago, http://forums.parallax.com/discussion/164364/prop2-family/p1 has PCB footprints of a number of suggested sizes.

    For the full Prop2, 100 pin 0.5 mm pitch is the first out the gate. As far as I can see, this has a 10x10 mm thermal pad. Which is what puts a hard limit of 8.5x8.5 mm on the die size. All ground pads on the die will be jumper bonded to the package thermal pad underneath.

    Next size down I get a common size hit of 52 pin 0.65 mm pitch. If so then this one would be a 6.5x6.5 mm thermal pad. Which in turn would presumable allow for 5x5 mm die size.

    Best match I've identified for the final 28 pin Prop2 in that picture is the SOP28EP with either 0.5 or 0.65 pitch. The 0.5 pitch thermal pad is 4x7 mm allowing for die size up to 2.5x5.5 mm. The 0.65 mm pitch has a skinnier thermal pad still so I'll discount it now.
  • evanhevanh Posts: 15,848
    edited 2017-04-09 05:03
    Reading a little more I see JMG also mentioned TQFP-32 as a decent alternative to the SOP-28. The 32 pin package at 0.8 mm pitch has a 4.5x4.5 mm thermal pad allowing for 3x3 mm die size.

    PS: For all parts I have assumed a fixed 0.75 mm(1.5 mm total) border space around the die is needed for the ground jumpers to be welded to the thermal pad.
  • evanhevanh Posts: 15,848
    edited 2017-10-08 01:17
    Here's the details on die sizing - http://forums.parallax.com/discussion/comment/1371876/#Comment_1371876
    and die layout - http://forums.parallax.com/discussion/comment/1372050/#Comment_1372050

    Both posted about the same time. I think my linking is date ordered but the forum software isn't too helpful in that dept.

    Also, the 3D files - http://forums.parallax.com/discussion/164113/prop2-layout-viewer-try-it-out

    More recently Chip has stated the available synthesis area is 7.7x7.7mm (59.29 mm2) - http://forums.parallax.com/discussion/comment/1421834/#Comment_1421834
  • evanhevanh Posts: 15,848
    edited 2017-10-07 01:44
    Chip has referenced the following as example packaging for the Prop2 - https://www.amkor.com/go/packaging/all-packages/exposedpad-lqfp-/-tqfp/

    Direct DL for the PCB design data - https://www.amkor.com/index.cfm?objectid=42EE3F1E-5056-AA0A-E24002DFF26966BD
  • cgraceycgracey Posts: 14,134
    Thanks for posting that, Evanh.

    I had never seen that PCB design document before that talked about the via array under the exposed pad. They recommend vias every 1.2mm in the array. For a 10mm square pad, that would be an 8x8 or 9x9 array. That's a lot of vias.
  • The following documents are about many footprints, but they also show some thermal data that clarify the benefits and tradeoffs involved in the design of the exposed pad contact area.

    Hope it helps.

    Henrique

    ti.com/lit/an/snva183b/snva183b.pdf

    https://onsemi.com/pub/Collateral/AND8432-D.PDF

    https://nxp.com/docs/en/application-note/AN4388.pdf
  • cgraceycgracey Posts: 14,134
    Henrique, those are great resources that make exposed-pad heat-dissipation matter very understandable. Thanks for posting those.
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