stevenvh

Member Since: November 30, 2010

Country: United States

  • Seconded. Without the ProtoBoard the Pi-Top is as closed as the next laptop. While the RPi has plenty of connectability none of it (including USB and Ethernet) is accessible from outside.

  • Looking at the pictures of the proto board it looks I was wrong about its connection.

    http://stevenvh.net/i/electronics/rpi/pitopproto03.jpg
    http://stevenvh.net/i/electronics/rpi/pitopproto04.jpg

    The 40-pin header does not go on top of the RPi. Instead it connects to the Pi-Top’s control board through a 34-pin connector at the left side, see

    http://stevenvh.net/i/electronics/rpi/pitopproto02.jpg

    The 34-pin connector’s pins are connected to a header at the right, so that several boards can be daisy-chained.

  • I’m new to RPi and Pi-Top, so bear with me.

    On the Pi-Top the RPi’s GPIO header is taken by a cable which connects to the Pi-Top’s power board. So you can’t use that (for now). Actually, apart from a couple of USB and a Ethernet connector all connectors on the board are used by Pi-Top. (And frankly USB and Ethernet don’t count since I have those on my Dell/Windows laptop too!)

    You probably want the Pi-TopPROTO board. It looks like it plugs onto your RPi’s GPIO header, and you plug Pi-Top’s cable on top of that. All connections are available on the board, and it includes a limited prototyping area. Solder your wires on the proto board and bring them into the Wild World at the right of the Pi-Top. Should be ideal for I2C or SPI at the least. I’ve looked around here on SFE, but I don’t think they offer the Pi-TopPROTO at this moment.

    Would be nice if somebody could confirm my conjectures.

  • 3.183 lbs in Trumpistan is 1.443 kg in all other countries. I weighed mine and it weighs 1.455 kg (including a RPi 3B), so that’s 12 g more. I guess the difference is because on mine the battery was full :-).

  • Not sure why you chose 433 MHz for non-Trumpian countries. The real European counterpart of 915 MHz is 868 MHz, not 433. Besides, the 433 MHz band has a long history and today is pure anarchy, probably the reason why it is being faded out, and AFAIK already illegal in certain countries. HopeRF has a 868 MHz version of the RFM69HCW, so do me a favor and replace that 433 by a 868 :-). Thanks!

  • If you don’t want to watch 1080p video then 1920x1080 is useless on such a small (13") screen. Note that on Windows laptops with this resolution and this screen size fonts are enlarged so that a typical screen layout will look like a… 1366x768 screen! If they wouldn’t enlarge the font text would become unreadable.

  • Possible yes. Reliable no, since you’ll be operating the RTC out-of-spec. So it may work, but don’t count on it. Most RTC ICs nowadays can operate from, say, 1.7V up to 5V. Maxim RTCs are exceptions.

  • The accuracy of an RTC depends on the crystal and load capacitors used, not the IC. The DS1307 has its load capacitors integrated, so there’s no way of tuning it there, then everything depends on the crystal tolerance. A typical 20 ppm crystal will drift up to 2 seconds a day, or 1 minute a month(!).

    There are RTC ICs with calibration registers which let you tune the frequency, like the Microchip MCP7940 and the NXP 85263A, to name a few. I guess that a couple of seconds per month is possible, provided temperature doesn’t vary much. The DS1307 can’t be calibrated.

  • Actually it’s New-Zealand’s spelling. The Brits just spell it as “schematic”.

  • Did you get/find an answer yet? I’d like to know this too.