Hello all,

I'm trying to get a handle on the current SOC/SBC options, but the
marketplace is so vast and bewildering, that I'm hoping I can get a few
quick recommendations of your favorites. We are developing an embedded
system in the domain of mobile environmental monitoring and need to put
together a proof of concept in December, so the components we are
currently looking for need not be the most optimal for production (i.e.
should be developer-friendly, but stil as small as possible). The
requirements are quite straightforward:

1) Sample a set of environmental sensors with outputs in the range of
0-5V, hence we need an analog/digital converter (ADC) with, say, 8
channels and at least 10-bits resolution. (To me personally, the ADC
component seems to be the critical hurdle.)

2) Get current position via GPS (this can be an integrated board, or
one attached by serial port or Bluetooth).

3) Wirelessly relay data to collection stations using TCP/IP,
preferably with Wi-Fi 802.11, but a GPRS interface would be an option
too.

4) The system must run off batteries and some of the sensors we are
considering need to be powered with 5V while others with 12V (for
development we need not more than one day of runtime; the vehicle has
its own power source).

5) All these components should be supported under GNU/Linux -- which
embedded distribution and development environment would you recommend?

6) It looks like we don't need much horsepower... 200MHz will be more
than enough, probably even a 486 will do (we are not considering
wireless sensor motes at this stage).

7) For prototyping, anything in the range of 200-500 $USD can go...

So far, I have looked at Gumstix and PC/104. The former looks smaller
and more interesting for our purposes... Any tips and insights will be
highly appreciated.

Thank you very much in advance.
--
/dima

On Mon, 24 Oct 2005 02:57:29 -0700, dimadiall wrote:

> Hello all,
>
> I'm trying to get a handle on the current SOC/SBC options, but the
> marketplace is so vast and bewildering, that I'm hoping I can get a few
> quick recommendations of your favorites. We are developing an embedded
> system in the domain of mobile environmental monitoring and need to put
> together a proof of concept in December, so the components we are
> currently looking for need not be the most optimal for production (i.e.
> should be developer-friendly, but stil as small as possible). The
> requirements are quite straightforward:

I can pretty much recomment the systems from embeddedarm.com - the TS-7xx0
(arm based boaards) meet your requirements nicely, except perhaps the
horsepower. And the price can't be beat - even with the 8 channel ADC
you're still below $200 in single unit quantities....

>
> 2) Get current position via GPS (this can be an integrated board, or
> one attached by serial port or Bluetooth).

If you figure this please let me know. I am looking for an affordable GPS
unit... Ideally a serial (RS485) capable, one that can be queried.

>
> 3) Wirelessly relay data to collection stations using TCP/IP,
> preferably with Wi-Fi 802.11, but a GPRS interface would be an option
> too.

Ditto for the GPRS; I would like to find an affordable board for this as
well.

> 5) All these components should be supported under GNU/Linux -- which
> embedded distribution and development environment would you recommend?

Standard Debian works well for me....

> So far, I have looked at Gumstix and PC/104. The former looks smaller
> and more interesting for our purposes... Any tips and insights will be
> highly appreciated.

I like gumstix, but the price of their add-ons drives them out of sight
for me....

Hi there Captain Dondo!

Captain Dondo wrote:
[...]
> I can pretty much recomment the systems from embeddedarm.com - the TS-7xx0
> (arm based boaards) meet your requirements nicely, except perhaps the
> horsepower. And the price can't be beat - even with the 8 channel ADC
> you're still below $200 in single unit quantities....

I checked their stuff and liked it a lot! Even the x86 boards (which I
am more familiar iwith) seem OK for my requirements as there is an
optional ADC unit.

> > 2) Get current position via GPS (this can be an integrated board, or
> > one attached by serial port or Bluetooth).
>
> If you figure this please let me know. I am looking for an affordable GPS
> unit... Ideally a serial (RS485) capable, one that can be queried.

I know little (yet) about RS-485, but stuff from sparkfun.com I was
looking at seems affordable to me and probably there is a way to hook
it up for your application. Check their GPS units here:
http://www.sparkfun.com/shop/index.php?shop=1&cat=63&

> > 3) Wirelessly relay data to collection stations using TCP/IP,
> > preferably with Wi-Fi 802.11, but a GPRS interface would be an option
> > too.
>
> Ditto for the GPRS; I would like to find an affordable board for this as
> well.

Same place, but a bit more expensive:
http://www.sparkfun.com/shop/index.php?shop=1&cat=75&

> > 5) All these components should be supported under GNU/Linux -- which
> > embedded distribution and development environment would you recommend?
>
> Standard Debian works well for me....

How small is your base OS (or how big is your CompactFlash)? Did you
ever try with other embedded distros (e.g. EmDebian)?

Do you have any experience with their own distro (TS-Linux)? Does it
support all included components out-of-the-box?

TIA!
/dima

On Tue, 25 Oct 2005 05:49:11 -0700, dimadiall wrote:

>> > 2) Get current position via GPS (this can be an integrated board, or
>> > one attached by serial port or Bluetooth).
>>
>> If you figure this please let me know. I am looking for an affordable GPS
>> unit... Ideally a serial (RS485) capable, one that can be queried.
>
> I know little (yet) about RS-485, but stuff from sparkfun.com I was
> looking at seems affordable to me and probably there is a way to hook
> it up for your application. Check their GPS units here:
> http://www.sparkfun.com/shop/index.php?shop=1&cat=63&

Thanks for the link. I'll forward it to the guys working on the GPS end
of things... (My job is just to make everything talk to everything else,
including the operator....)

RS485 is a serial bus... It communicates much the same was as RS232, but
you can have 32 units on a single serial port (actually more, but that's
what the spec says) and it can be used for much longer distances. It only
takes 2 wires, and is mostly immune to noise.

>> > 5) All these components should be supported under GNU/Linux -- which
>> > embedded distribution and development environment would you recommend?
>>
>> Standard Debian works well for me....
>
> How small is your base OS (or how big is your CompactFlash)? Did you
> ever try with other embedded distros (e.g. EmDebian)?
>
> Do you have any experience with their own distro (TS-Linux)? Does it
> support all included components out-of-the-box?
>

They provide a kernel and source which supports all of the stuff on the
board. They also provide sample user-space apps for accessing various
things. All in all it's a pretty neat package, and it works really well.
I'm impressed so far.

I have not played with TS-linux, opting instead for the debian install
they provide, along with the cross-tool kit. The cool thing is that they
don't change more than they have to, so you can pretty much use anything
you want with the exception of the kernel....

I like debian because it comes in every flavor you can want. We will
probably port our stuff to x86 as well as ARM so that we have
multi-platform support (our life cycle is such that end-of-life for ARM
and x86 is a concern).

I am hoping to get my apps+OS into 8MB. That might be a stretch, seeing
as I have to have RS232+RS485 support, a windowing system to drive a QVGA,
communications with modbus equipment and propriatary PLCs, VPN, ethernet
(both UTP and PPP over radios), two GPS units, a compass, a cell phone, a
web server and a way to generate dynamic web pages, and enough smarts to
generate the web pages for either a PC or a cell phone, SMS messaging,
HMI with keypad and joystick support.... You get the idea....

Yeah, I get the idea... Our app will be much simpler to start with --
read the sensor on regular intervals and upload data with location
coordinates to server. Later it may get more complex, if the
robot/vehicke is to be controlled autonomously.

Thanks for sharing your thoughts on this. There are still many aspects
to sort out, but your recommendation apparently will save my day!!
/dima

On Mon, 24 Oct 2005 11:57:29 +0200, <dimadiall@gmail.com> wrote:

> 6) It looks like we don't need much horsepower...

looks like a perfect application for a 10MHz Atmel to me

--
I really have no idea what this means. And since I can't install linux on
it, I'm gonna go back to surfing pr0n.
the penguins are psychotic / just smile and wave

dimadiall@gmail.com wrote:
> Yeah, I get the idea... Our app will be much simpler to start with --
> read the sensor on regular intervals and upload data with location
> coordinates to server. Later it may get more complex, if the
> robot/vehicke is to be controlled autonomously.

How many channels? What is the maximum sample rate per channel? That
would help to determine whether you need an 8 bits PIC/AVR or 32 bits
ARM/PPC/X86. Do you ned FIR or FFT filters?

>
> Thanks for sharing your thoughts on this. There are still many aspects
> to sort out, but your recommendation apparently will save my day!!
> /dima