Beagle Bone Black: $45 -- Raspberry Pi/Arduino alternative

[j]

This caught my attention:

http://www.extremetech.com/extreme/...i-and-arduino-on-a-single-board-for-just-45/2

Roughly, it is a faster version of a Raspberry Pi with an Arduino like
GPIO. And for $10 more than a Raspberry Pi.

I got my Raspberry Pi a week ago and I was blown away by the
possibilities of just that. And previously amazed at the Arduino.
Sensors and servos are so readily available and cheap that all kinds of
control projects are doable. There is already a huge amount of open
source code ready for the download. It's evolutionary and revolutionary
for small players like myself (and some of you guys!).

Jeff

 

[Neon John]

This caught my attention:

http://www.extremetech.com/extreme/...i-and-arduino-on-a-single-board-for-just-45/2

They're gouging. TI has the Black on their site for $35, the official
list price.

I'm designing our company's next generation induction heater around a
BB White so I'm intimately familiar with the product. It is being
sold as a general purpose system-on-a-board (SOB) but it is not. The
embedded Linux is barely complete enough to run the Ethernet and
generate a login prompt. For anything else plan on being a kernel
hacker. I've had to hire a programmer to write a custom SPI port
driver because the included one (which only uses 1 of the chip's 3
ports) is barely functional.

To get audio and video from either the White or Black, one has to buy
"Capes" (expansion boards). The driver support is fairly poor from
what I'm reading on the support list.

I've avoided the Pi because it isn't open source and because of the
hype but I think that if you wan an SOB that you can just turn on and
use, the Pi is probably the answer.

John
John DeArmond
http://www.neon-john.com
http://www.fluxeon.com
Tellico Plains, Occupied TN
See website for email address

 

[j]

They're gouging. TI has the Black on their site for $35, the official
list price.

I couldn't find it there. I saw the old model for $89.

I'm designing our company's next generation induction heater around a
BB White so I'm intimately familiar with the product. It is being
sold as a general purpose system-on-a-board (SOB) but it is not. The
embedded Linux is barely complete enough to run the Ethernet and
generate a login prompt. For anything else plan on being a kernel
hacker. I've had to hire a programmer to write a custom SPI port
driver because the included one (which only uses 1 of the chip's 3
ports) is barely functional.
YIKES.

To get audio and video from either the White or Black, one has to buy
"Capes" (expansion boards). The driver support is fairly poor from
what I'm reading on the support list.

This claims it has a micro HDMI out (no separate audio):

http://www.bit-tech.net/news/hardware/2013/04/24/beaglebone-black/1

I've avoided the Pi because it isn't open source and because of the
hype but I think that if you wan an SOB that you can just turn on and
use, the Pi is probably the answer.

There's a ton of stuff for it (Pi) on Github, including openCV (which
should run on BB) and openBR, which suits my fancy. Also a choice of
OS's. Raspbian Wheezy is functional and runs Libre Office, as well as
the Chromium browser, albeit slowly for a complex site. The USB is
crippled though and loses bandwidth dropping packets.

What caught my attention on the BB was that it could stream HD. I was
clueless on the driver/software support but didn't imagine that it was
that bad.

My uses for it are a mix of art and AI. I've made some remote control
mobiles with the Arduino and have some solar thermal control stuff to do
with that as well. This all still excites me as the possibilities are
endless, 40 years ago I was etching boards and using the first gen ICs,
this is so much easier and more powerful.

Thanks,
Jeff

 

[j]

On 4/26/13 9:41 AM, Neon John wrote:

I bought a BB White for my project and ended up shelving it in favor of
an Arduino Mega 2560 so as to have the I/O I wanted on-board. I wasn’t
keen on spending a lot of time kernel hacking and managed to get by with
rolling my own (minimal) clock and cooperative multitask scheduling
routines. You can see some of the C source at

The scheduling is very cool.

http://www.iedu.com/Solar/LENR/Code.html

RaspPi isn't bad for GPIO:

https://www.dropbox.com/s/m5l185qxq9w5mzk/raspberry-pi-gpio-cheat-sheet.jpg

There is a lib that gives 8 PWM outs (shares a timer), I don't think you
needed that though.

On the other hand, logging and WiFi and having memory to burn (and
Python as a high level wrapper) is very cool and easy.

 

[Neon John]

I wish I’d known that you needed an SPI driver because I have C code
here (written to talk to an X25650 EEPROM) that would have been fairly
easy for you to rework to suit your needs.

Thanks Morris.

What I needed is somewhat specialized. I'm sampling an analog signal
at 1 megasample/sec using an Analog Devices SPI A/D converter. The
SPI clock is the sample trigger so it has to be precisely on frequency
and of low jitter. If not, the FFT that follows is all over the
place.

The SPI driver that comes with the board runs at a low priority and
the preempting causes as much as half a clock cycle jitter. Totally
unsatisfactory.

I worked on the problem for a couple of weeks, time lost to the
product design, when I reminded myself that I'm a EE and not a kernel
hacker. I found a guy in England who is a kernel expert and did the
driver in just a few hours. We took a very simple approach. The size
buffer is programmed with an IOCTL call. The buffer is in kernel
space. When the call to take a sample is made, everything else is
preempted while the driver runs the port for the designated number of
samples.

There is still some clock jitter resulting from phase-locking a (I
think)24 MHz crystal up to 700MHz and then back down to the 48 MHz SPI
clock. But the FFT smear is tolerable for this application.

The important point I wanted to make is that the BeagleBone is not
souped up Arduino as it's being called. It's only for Linux experts
(or those who want to be) and certainly not for someone inexperienced
in Linux internals who is just trying to get a project done.

I could write many more paragraphs but I'll stop here. The only
reason I've stuck with it is that I need the raw speed and the
built-in "neon" DSP instructions.

John
John DeArmond
http://www.neon-john.com
http://www.fluxeon.com
Tellico Plains, Occupied TN
See website for email address

 

[j]

http://www.extremetech.com/extreme/...i-and-arduino-on-a-single-board-for-just-45/2

So, I hesitated and then bought a BBB.

It came loaded with Angstrom 3.8.6 and a few basics loaded on the eMMC.
I needed to buy a power USB hub and a micro HDMI adapter. Otherwise
getting to a desktop was painless. It boots into Gnome and has the
basics installed.

It runs much snappier than the Pi, (but I had the Pi on a class 8 SD).
The performance monitor on the BBB rarely shows 100% CPU, and the Pi
often did. It has a lot more chips on the board than the Pi, so things
like the ethernet aren't shared with the USB. All the needed hardware is
there.

With that said, working on the Pi, installing software and updating the
kernel is much easier on the Pi and Raspbian Wheezy. The Pi community
and support is better thought out. And, the BBB is very new and there
are some bugs and such.

I suppose if I moved to a different distro like Ubuntu this would be
better, but Angstrom seems a better match for tinkering.

The GPIO is mind boggling. I haven't gone cape shopping yet. I'm looking
for something simple.

Jeff