[arm-allstar] Nano Allstar Interface Howto

Doug Crompton wa3dsp at gmail.com
Sat Dec 3 13:15:38 EST 2016


Joshua,

  Well it is in the howto's hardware sub-section of the page.

The new code will be in-place update-able. We have not decided yet whether
the nano will be in the initial image release or an update shortly
thereafter. Either way it will be soon. Also test software for the Nano
will be out soon.

As far as problems with EMI in/out of the Pi GPIO ports. I have no hard
evidence of it but our decision was it was better design practice to not
have leads from the Pi GPIO going distances to outside I/O. Even with the
current (USB) control there have been problems with high power RF.  Good
shielding, ferrite's, and lead dressing usually solved the problems.  It is
also a lot less expensive to replace a $3 Nano board than a Pi.

Also mentioning EMI, my howto has no bypassing. This is consistent with the
simple USB FOB mod also in the howto's. Most people do not have problems
but if you do bypassing (.01) the I/O leads to the radio might be a good
idea. You could also use ferrite beads on the I/O leads in and out of the
case.

A couple of things I did not mention in the howto, but I will add, was that
the USB sound FOB is mounted such that a peep hole on the top side shows
the green heartbeat LED for the FOB and the COS/CTCSS LED's have direct
feedback from Allstar. This means they will always follow properly and
light when a signal is present. No need for jumpers. This also makes setup
very easy as you would set the carrierfrom=usb|usbinvert and observe that
the COS LED lights on keyup. More of this in the revised setup docs coming
out.

My next build is a two port, using two FOBS, Nano, and a mini USB hub all
in one box for a two node one USB connection solution.


*73 Doug*

*WA3DSP*

*http://www.crompton.com/hamradio <http://www.crompton.com/hamradio>*

On Sat, Dec 3, 2016 at 12:43 PM, "Joshua Nulton via arm-allstar" <
arm-allstar at hamvoip.org> wrote:

> Small typo Doug, the article is located under the hardware section not the
> how to section. But regardless you had posted a direct link anyway, I just
> didn't notice that the first couple times I read it.
>
> Very excited for the upcoming update, I really think this ATmega addition
> will be looked back upon as one of the major milestones of the project, as
> some would say "it's gonna be HUGE".
>
> At this point with the hardware soldered up, we are not manually sending
> any code into the Arduino yet, or I didn't see any code posted. Should I
> assume that the ARM update that is forthcoming will do this for us, or is
> it just not ready for a prime time public release just yet?
>
> Lastly I just want to say excellent article, I thoroughly enjoyed reading
> it in it's entirety three times, you are a great teacher and writer. I am
> curious about the spurious RF off the GPIO ports of the Pi itself that you
> mentioned in the first paragraph, were these emissions actually causing
> errors and interference or were they just too erratic on the scope for your
> comfort levels?
>
> Joshua KG5EBI
>
>
> arm-allstar mailing list
> arm-allstar at hamvoip.org
> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
>
> Visit the BBB and RPi2/3 web page - http://hamvoip.org
>
>


More information about the arm-allstar mailing list