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KISS Eval board (general discussion) - Page 2 — Parallax Forums

KISS Eval board (general discussion)



  • Capt. QuirkCapt. Quirk Posts: 872
    edited 2020-10-01 21:08
    Has anyone else had problems with male pin headers and female
    DuPont wires?

    There are many Arduino boards that use male pin headers for I/O
    connections. They work fine with a bread board, but maybe not with
    DuPont wires.

    My female DuPont wire connections fail ~60 to 70% of the time. So
    now I modify every female wire connection before I use one.

    Bill M.

    Or perhaps many of the board manufactures choose a pin diameter
    that works for bread boards, but may be on the small size for some
    brands of female DuPont wires.
  • I always used the standard pin headers with 0.1" pitch and 25 mil square pins. They fit the female DuPont connectors exactly but need some force to be inserted into a breadboard, especially if there are many in a row. But I never had problems, I mean the contact springs of the bread board are not over-bent.

    Smaller pins are easier to insert but probably fail with DuPont wires.
  • Dave HeinDave Hein Posts: 6,347
    edited 2020-10-06 01:34
    @ManAtWork, would it be possible to do a P2 board like this, where the port A I/O pins would be on the outer row of pins, and port B would be on the inner rows? This would allow making a DIP with just two rows of pins if less than 33 I/O pins are needed, or pins could be put in all four rows if more I/O is needed. The 40-pin DIP version would be nice to use on solderless bread boards.
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  • ManAtWorkManAtWork Posts: 2,011
    edited 2020-10-06 07:37
    Well, it would be possible but a lot harder to route because most of the A and B port pin traces would cross each other. You could also do a DIP style plug in board with only two rows with the current layout. The difference is that it would use all even (or odd) pins instead of only port A (or B ) pins.

    The disadvantage is that there are some cases where continous pin groups are required, like USB (requires even/odd pairs) or when you need the full range of -3/+3 smart pin routing. In that cases you can use jumper wires to access the missing pin numbers. The advantage is that the current layout is compatible to the accessory board connectors.

    If there are no objections I'd order some (empty) PCBs, today. It doesn't cost much compared to the time I've already invested. We can decide later if I assemble them or not. Peter says, the P2D2 is almost ready to ship but I've heard that before. :blush:
  • ManAtWork wrote: »
    Peter says, the P2D2 is almost ready to ship but I've heard that before. :blush:

    I do believe I will have blank sets of pcbs in my hands this week. JLCPCB indicate production is complete on all pcbs and stencils and it is being shipped out via DHL Express Priority which I find are the fastest and the best for me. I will make up test boards immediately. What's interesting is that on the order progress page that you can click on the progress of each job and then mouse over the process and it shows a video of what typically happens with this process.
  • Dave HeinDave Hein Posts: 6,347
    edited 2020-10-06 11:23
    @ManAtWork, I realize that your goal was to allow for plugging in the Eval accessory boards. I'm thinking more along the lines of a P2 EDGE, but with DIP connectors. I think that it would be useful have a DIP board with a minimal footprint size. Here's another pin grouping that might be easier to route, and provides consecutive pins in groups of four.

    I think this board would be cheaper to make than the P2D2, and the DIP version is compatible with solderless bread boards. The double DIP configuration would be access to all of the I/O pins. I don't think the latest version of the P2D2 allows for 0.1" pin spaces.
  • Dave, do you think that layout would have enough advantages over the P2DIP40 and P2DIL80 to justify a redesign? I'm getting more and more pessimistic if it's still woth doing anything now that there are more competing boards every day.
  • ManAtWork - you're not being pessimistic. You're more like being realistic. Bear in mind, however, that what we see is not boards, it's designs. Makes a difference. We're yet to see the actual boards.
  • ManAtWork wrote: »
    Dave, do you think that layout would have enough advantages over the P2DIP40 and P2DIL80 to justify a redesign? I'm getting more and more pessimistic if it's still woth doing anything now that there are more competing boards every day.
    I haven't seen the specs for the P2DIP40/P2DIL80, but it looks like what I've been asking for. Hopefully the P2DIP40 will provide consecutive groups of pins for I/O modes that need them.
  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2020-10-07 12:31
    Designs they may have been, but boards they now are and they are on their way as we speak and parts are all in stock. Besides I have a lot of earlier P2D2 board versions made up and they have worked since the original P2D2 that the first P2 chip was tested on. The design has been constantly improved to a point where those improvements don't compromise the design or force the cost up and now I have the one standard module that can be manufactured in volume but adapted in so many different ways.
  • Dave HeinDave Hein Posts: 6,347
    edited 2020-10-07 12:45
    Peter, I didn't realize you designed the P2DIP40/P2DIL80. Was this designed based on the P2D2 without the uSD, USB, RTC and clock generator? That's a good idea to have a slightly lower cost solution available. Sorry, I haven't been paying much attention to what's available lately.
  • The P2DIP40 and P2DIL80 are mine, i'll talk about those later today
    Is the P2 QUIP yours or Peters? It gets confusing, I don't want to assume

    Regarding the i/o numbering on P2DIP40 and P2DIL80 - there are two counterclockwise circles of I/O at the edge
    - the inner circle is P2 Port A (P0..31), same as P8x32A-D40 (P1 DIP40)
    - the outer circle is P2 Port B (P32..63)

    The advantage of having Port A on the inside is you can work with existing P1 DIP40 designs, breakouts. Its plenty stable in breadboards and you gain a couple of extra rows of holes on the breadboard (that tuck just under the overhang). Some photos will help illustrate this better

    A second advantage is that is makes it effortless to create hybrid P1 & P2, 16 cog beast. Any compatible board eg P1 Flip, Phil's Propstick or Propstick USB can sit atop or below the P2 plane, with the benefit of using the right generation of cog for each job at hand. It sounds more frankenstein than it is in practice
  • IMHO, Frankensteins tend to be seen as "different", because we look at them as being a single-instance, by nature.

    A whole population, composed by many Frankenstein-alike beings, is, well, just another new people in the city!

    Just say welcome to any P2-Frankies! :lol:
  • Dave HeinDave Hein Posts: 6,347
    edited 2020-10-07 16:25
    @Tubular, P2 Quip is just a name I used when I morphed the drawing for the P2 Edge into a drawing for a 4-row 80-pin board. After looking at Peter's P2D2 thread it looks like he uses the same name for one of his adapter boards. I like the idea of the P2DIP40/P2DIL80, and I'm looking forward to seeing more information on it. From my point of view it's a good thing to have a variety of P2 boards. It will help get the P2 into the hands of hobbyist and product developers.

    @ManAtWork, sorry for hijacking your thread. I think your KISS Eval board has merit also. For people that don't need USB and SD, it should cost less and be more compact than the current P2 Eval board.
  • Designs they may have been, but boards they now are and they are on their way as we speak and parts are all in stock....

    Just to be clear, I wasn't thinking of your boards, Peter (these I know exist for real).

    Quite the opposite - I mean, are there any other P2 boards we are discussing here (save the Parallax P2 Eval which does not fall in this category) in physical existence ready to flood the market in, say, 2-3 weeks from now ? Which ones ?

    They do exist as design concepts all right but nothing more or at least that is the impression I take from what is being said here. Some are closer to become a reality but others might not get that far for various reasons.
  • @ManAtWork - I'll be happy to have your board (exactly as you described it in the initial post) as much as I'll be happy to have Peter's P2D2. I have good use for both. I just agree with your assessment of the current situation. I'd wait and see and then decide the next steps. That's all.
  • JLC messed up shipping my boards. :neutral: I ordered 10/7 and today the PCBs have arrived. It took over a month!

    Anybody still interested?
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  • I thought you've abandoned the idea but since you apparently have not then I'm in.

    We can work out the details later on. Just shoot me an email at your convenience.
  • It was originally meant as quick fix until peters R2D2 is finally available. Now, he nearly catched up. Let's wait until tomorrow.

    But I ran at least one panel on the P&P machine, today. To good to throw it all away...

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  • PublisonPublison Posts: 12,366
    edited 2020-11-10 18:00
    Looks great! Are those Rev B or C chips? If you want to pursue North America distribution, I'm in to do that.
  • Heck, I wish I had more money :). They look so nice on the panel. Thanks for posting this.
  • RevC. I'll check if they work, tomorrow. I could make up to 60 this week but I doubt that there is much demand.

    The mixed top/bottom single row headers are for breadboarding. The double row headers are for P2EVAL style accessory boards.
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  • Very nice!
  • @ManAtWork

    Please, hold on to this statement of yours:

    "Because of the different pin header options everybody has to solder the THT parts by himself."

    I'm writing this just in case :smile: . I see this as a very valuable option to have.
  • Cluso99Cluso99 Posts: 18,066
    Looking good :)

    Personally, almost every board I buy I wish they didn’t have the headers soldered, just included loose. I often want to change the headers to female, install only a subset, or something even different again. It’s a pita to remove if you want to put sockets in instead, or right angled pins, or whatever. So go for it!
  • This is a very good design. Simple, basic, yet flexible.

    Would be very easy to use as a brain board for custom applications with a simple carrier board it could snap onto.

    Your pin / header layout is the best I have seen so far in the boards offered or theorized for adapting to embedded designs or prototyping with.

    I would be interested in getting one depending on final cost + shipping to the US.
  • AAaaarrrggg! :( Murphy got me. The P2 is mounted in the wrong direction. Pin1 should be in the upper left corner but it is in the lower left one. I didn't notice because
    a) most of my P1 designs have the propeller rotated 90 CCW, so it looked "as always".
    b) on my new P&P machine 0° rotation means pin #1 in the upper left corner where on my old machine it meant lower left corner. The trays have pin #1 in the lower left so I thought the default setting (0°) for the pickup position was right. But it wasn't. It should be -90°.
    Note to myself: Always double check every IC on the first run! Always double check...

    Outcome: one burnt P2 chip, 4 PCBs I have to fix...
  • Ok, I assembled another panel, this time with the P2 in the right orientation. 2nd smoke test was successful. Voltage regulators work, flash and oscillator also. :smiley:
  • Cluso99Cluso99 Posts: 18,066
  • ErNaErNa Posts: 1,737
    Just Not all Pins are equal 😊
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