[time-nuts] looking for low-power system for gps ntp timekeeping

[Iain Young]

On 02/07/13 06:43, NeonJohn wrote:

> Before anyone wastes his money on a BeagleBone, I suggest you join the
> mailing list and read the hundreds of messages each day that pass
> through, most of them citing problems, mostly with the Linux implementation.
>
> Basically, the ancient implementation of Angstrom Linux is a POS.  Just
> barely enough code to be able to say, for example, that SPI works.  It
> does - sorta - but not well enough for any application where clock
> timing or jitter matters.

You are not restricted to just Angstrom. My fleet run Debian. FreeBSD is
also available. First thing I do is blow away Angstrom from any SD card.

> I had intended to embed the BB white in my next revision induction
> heater.  After several months of frustration and a considerable amount
> of money to a kernel programmer to write drivers that actually worked, I
> gave up.  I could easily had a man-year in the application that I can do
> bare metal in a few months.

Hmm, is this a case of Angstrom being beind the kernel curve, or is it still
an issue when running things like Debian ? I've not had the need to use
SPI on the BB yet, only the Pi.

> The thing that finally canned the BB for me was the short SD card life.
>   Even though the implementation uses a virtualized root file system, it
> still writes to the SD card about once a second.  The result is that
> even industrial grade SD cards rarely live over a year.  With the Black
> they tried to address the problem by putting some NAND memory on board
> but that only prolongs the problem and with components that are not
> easily changed.

I've only ever had one SD card go dead on me on my entire fleet, and I
suspect that was actually my fault, not Debian's :)

  > A final negative is the support.  The team member, a guy named Gerald,
> who provides official support on the mailing lists is one of the most
> hateful persons I've encountered on the net. No, I never personally had
> an encounter with him but I daily shook my head in amazement that TI
> would let such a person rep them.
>

I've heard he can be somewhat robust to deal with. That said, he is
very knowledgeable from what I've seen/understand. Never actually had
to mail the mailing list itself though - found all the answers I needed
in the archive - often from him!

> PS: Before you go to buy the Black, take a careful look at what all they
> left off in an effort to compete with the Pi.

Hmm. I checked a lot of the things I'd need on the black for this type of
application, and found they were all still there (Serial Ports, PRUSS,
Timers etc). Yes you may need to twiddle the pinmux as by default it
goes to  he HDMI stuff etc, but they are still there

Is there something specific here you are thinking of ? Maybe I just
don't need what they left off. I do remember looking and going "Meh,
not important for what I'm doing"


Best Regards

Iain