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Charitable donation for memory and display boards

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Comments

  • RaymanRayman Posts: 12,818

    Tried a bit with 24 MB on P8, no luck.
    Need a faster way to test...

  • Wuerfel_21Wuerfel_21 Posts: 3,131
    edited 2022-09-10 21:45

    Should try with the 96MB board (or just USE_PSRAM_SLOW in general, though 4bit/slow will make NeoYume unhappy).

    I don't think anyone has gotten external RAM to work on an Edge board. (I only have a Rev.A regular Edge and the big JohnnyMac breadboard, which is a nonstarter anyways). Then again, the 32MB Edge exists.

  • RaymanRayman Posts: 12,818

    24 MB works on rev.c edge board. See pics from a few posts ago

  • I meant "work reliably"

  • RaymanRayman Posts: 12,818

    Tried to get this P2 board made with 3 oz copper. But, they wouldn’t do it because pads ( on P2 I presume) are too close together.
    Have to settle for 2 oz. May or may not do NeoYume.. will be interesting to see.

  • RaymanRayman Posts: 12,818

    They wouldn’t give me 2 oz on top and 3 oz on bottom either. Has to be same on both sides…

  • evanhevanh Posts: 13,574
    edited 2022-09-14 23:53

    Larger diameter vias should help. They'll have more copper per via and the added solder fill will increase heatsinking too. EDIT: And if you are getting them assembled for you then lead-free solder will be better heat conductor as well.

  • RaymanRayman Posts: 12,818

    Lead free better heat conductor?
    Didn’t know that.
    By how much?

  • evanhevanh Posts: 13,574
    edited 2022-09-15 13:31

    It was a guess but Lead is not great at conducting anything, while Silver is going to be good since it's the best electrical conductor.
    Looking them up - https://en.wikipedia.org/wiki/List_of_thermal_conductivities I find lead-free-solder listed as 60. Disappointingly a long way short of its component metals. And with leaded solder at 50 they're not far apart.

    EDIT: Personal experience tells me that stated figure might not be correct. My impression of soldering with lead-free is the heat travels much quicker than with leaded solder.

  • VonSzarvasVonSzarvas Posts: 2,776
    edited 2022-09-15 17:28

    @evanh said:
    EDIT: Personal experience tells me that stated figure might not be correct. My impression of soldering with lead-free is the heat travels much quicker than with leaded solder.

    >

    Maybe related to the hotter iron / air ?

  • evanhevanh Posts: 13,574
    edited 2022-09-16 02:27

    hmm, possibly. I dunno where my roll of lead-free is these days. It might be 20 years since I last used it.

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