Troubleshooting “digispark” (ATtiny85) on Mac OS X

attiny85-breakout-boardIf you encounter problems programming your “digispark” this info might be helpful. First of all I will assume you have followed the getting started guide on the Digistump wiki (Connecting and Programming Your Digispark). Should you after completing these steps experience issues with programming your “digispark”, check out these basic troubleshooting tips (try different cables, USB hubs etc).

In addition to the tips mentioned above you might also experience an error similar to this:

java.io.IOException: Cannot run program "/Users/{USERNAME}/Library/Arduino15/packages/digistump/tools/micronucleus/2.0a4/launcher": error=13, Permission denied

If you get this error this might be caused due to security restrictions and you need to make the micronucleus tools executable on your machine. Run the following commands (your actual path may vary, i.e. due to a different version of micronucleus):

$ cd ~/Library/Arduino15/packages/digistump/tools/micronucleus/2.0a4/
$ chmod a+wx launcher
$ chmod a+wx micronucleus

Complete error message:

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Your First Raspberry Pi: A Buyer’s Guide

Pi_2_Model_BI found this great post about the choices you need to make when buying your first Raspberry Pi. Although being a great guide when deciding about which model to choose and what complementary hardware you need, it is a bit outdated. I would recommend you read the guide, however with following additions:

Model A vs A+

This is the differences with A+ compared to the initial Model A:

  • More GPIO. The GPIO header has grown to 40 pins, while retaining the same pinout for the first 26 pins as the Model A and B.
  • Micro SD. The old friction-fit SD card socket has been replaced with a much nicer push-push micro SD version.
  • Lower power consumption. By replacing linear regulators with switching ones we’ve reduced power consumption by between 0.5W and 1W.
  • Better audio. The audio circuit incorporates a dedicated low-noise power supply.
  • Smaller, neater form factor. We’ve aligned the USB connector with the board edge, moved composite video onto the 3.5mm jack, and added four squarely-placed mounting holes. Model A+ is approximately 2cm shorter than the Model A.

Recommended for embedded projects and projects which require very low power, and which do not require Ethernet or multiple USB ports.

Mode B vs B+

Model B+ should not be mixed up with the Model B Rev 2 (which is simply a slightly updated Model B rev 1with minor differences). However, the differences between Model B and B+ is on the other significant.

  • More GPIO. The GPIO header has grown to 40 pins, while retaining the same pinout for the first 26 pins as the Model A and B.
  • More USB. We now have 4 USB 2.0 ports, compared to 2 on the Model B, and better hotplug and overcurrent behaviour.
  • Micro SD. The old friction-fit SD card socket has been replaced with a much nicer push-push micro SD version.
  • Lower power consumption. By replacing linear regulators with switching ones we’ve reduced power consumption by between 0.5W and 1W.
  • Better audio. The audio circuit incorporates a dedicated low-noise power supply.
  • Neater form factor. We’ve aligned the USB connectors with the board edge, moved composite video onto the 3.5mm jack, and added four squarely-placed mounting holes.

The Model B+ is perfectly suitable for use in schools: it offers more flexibility for learners than the leaner Model A or A+, which are more useful for embedded projects and projects which require very low power, and has more USB ports than the Model B.

The New Raspberry Pi 2

The Raspberry Pi 2 is the next generation of Model B/B+, and it is not even mentioned in the original post. It basically is a beefed up Model B+ with better CPU and more RAM, making it even more suitable for HTPC, NAS and similar usages.

Because it has an (quad-core) ARMv7 processor, it can run the full range of ARM GNU/Linux distributions, including Snappy Ubuntu Core, as well as Microsoft Windows 10. And due to being more powerful the “Pi 2” will be slightly more power-hungry compared to the Model B+ (up to about 0.5-1w more), and especially compared to the Model A+.

Original post

http://computers.tutsplus.com/tutorials/your-first-raspberry-pi-a-buyers-guide–mac-54134