Category Archives: Uncategorized

Simple Hardware Prototyping

Eventually, while wandering down the crooked path of Single Board Computing or audio, you will probably want to make your own board or simply wire some things together.  While a seemingly simple task, you’ll soon find out some of your choices for hardware are not always so friendly.  What if you don’t know what configuration you want in the end?  What if you’re on a budget?  Well, take a chair.

First things first, never embark on this journey without a bread board.  If you have the budget, get a big one.  If you’re starting completely from scratch, take a look at this one.  If you can’t really spare much, I use one like this nearly daily for simple things.

Alright, next up.  The kits I linked above have some power supply options included, quite clever and I’m a fan.  I think I’ll build a similar thing, with a higher current rating and some thought involved (putting an amp through a single breadboard pin is… not the greatest idea, so probably 3).  Point-point wiring is part of breadboarding, so solid-core wire is a plus.  You can also grab a set of jumper wires with male and female ends.

Moving on, a lot of SBC’s from FriendlyELEC have USB headers on board, you can snag those as well on Amazon.  I use Amazon a lot, but these things can be had from all of the various large global online retailers.

A lot of these little things have either flimsy pins like the USB connectors, or wide terminals like some rotary encoders I purchased, or are not even “through-hole” devices at all.  For the standard pitch items I use Prototype PCB boards with header pins to provide some robustness against the prototype process, because no one wants to be constantly breaking things and buying new parts.  Examples of using these boards:

The rotary encoder has wide flat terminals that barely fit into the prototype board, and would not fit into the breadboard.

Notice the skinny boards are perfect for the USB connectors because the hole spacing aligns for the shroud tie-down and the board.

Shown in a breadboard, however obviously without any connecting wires.  A word of caution concerning USB I’ve given in other posts:  It is a differential signal, the D+/D- wires have to be the exact same length, or the signal gets destroyed by being out of phase.

As a last note, I almost forgot an extremely useful little gadget:  the surface mount to through-hole adapter.

 

And probably a soldering iron.

General Updates

General updates, I have not been active enough.

Firstly, the default 4.4 kernel for Tinker board now supports the Raspberry Pi 7″ display out of the box.

I have purchased a NanoPi Duo, a board I am interested in because I personally enjoy embedded applications, to the point where I prefer not to have the built-in connectors, it’s harder working around them than it is to add them later on.  I’ll have a review of that after bit.

Le Potato:  Armbian Next images (4.13) available, I am looking into using the mainline u-boot being worked on by Bay Libre (current Amlogic official U-boot is 2015.1)

Tinker Board Update Armbian Kernel 4.12

I’ve kept working on the Tinker Board, and with a nudge from Myy , have gotten the WiFi driver to work on Armbian under kernel 4.12.  In 4.12 the RTL8723bs driver was added to Staging, so it can be enabled without any patching to the kernel itself short of the device tree for the Tinker Board.  Now for that pesky reboot bug and Bluetooth…

As always, give me a yell over at the Armbian forums,

NanoPi NEO Air Tips, Tricks, Info

My NanoPi NEO Air arrived a few days ago, I waited until I also received a wireless antenna to go with it (Not included with the board)  I was immediately excited to try out the 8 GB eMMC built onto the board, however that proved to be a challenge to research.  Using the images provided by FriendlyElec, and their instructions, a flash could be done, but I wanted to use my preferred distro at this point, Armbian.  After some forum surfing, I determined the work had been done for me.

Step 1:  Download a copy of the Armbian image and burn it to an SD card.  Stick it in the NEO Air.

Self explanatory I think.

Step 2:  Using a USB3 port (preferably), power your NEO Air.

There is a reason for this.  The good folks at FriendlyElec made the microUSB you associate with powering the device an active USB port.  The better folks over at Armbian made that default to a USB/Serial endpoint at 115.2 kbps.

***Caution***  If you’re getting a blue heartbeat, the device needs restarted, the serial port won’t be there.

Once you have a solid green, you should see a new serial port in your device list.  Talk to it, and you’ll be able to log into your NEO Air’s command line.

Step 3:  Create Users/Housekeeping

Step 4:  as su:    “/usr/lib/nand-sata-install/nand-sata-install.sh”

That will stuff the image onto the eMMC.  After a few questions, like what sort of filesystem to use, it will let you know when it can be shut down.  Pull out the SD, reboot.

 

The eMMC is *A Lot* faster than the SD card, so that is a plus.

 

One last note:  The analog audio is still available, although I’m not a skilled enough soldering master to attempt it.

 

 

See the 4 small round pads up next to the camera connector?  Yep, Line Out and Microphone In live there.  This was pointed out to me by the folks over at the Armbian forums, unfortunately their webpage is having some issues at the moment, so I can’t provide the link to the info.