Arduino Forum

Development => Other Hardware Development => Topic started by: jluciani on Mar 26, 2011, 07:55 pm

Title: PICOBEE
Post by: jluciani on Mar 26, 2011, 07:55 pm
First new board of Spring -- PICOBEE
'328  (Arduino bootloader) + RTC (with battery backup) + XBee

(http://wiblocks.luciani.org/PICO/images/picobee_top_256x256.jpg)

Prototypes should be in around 2-3weeks.
Details at http://wiblocks.luciani.org/PICO/PICOBEE-index.html (http://wiblocks.luciani.org/PICO/PICOBEE-index.html)

(* jcl *)
Title: Re: PICOBEE
Post by: frank26080115 on Mar 26, 2011, 09:19 pm
interesting, what kind of applications are you thinking about that involves wireless combined with a RTC?
Title: Re: PICOBEE
Post by: mowcius on Mar 27, 2011, 03:29 pm
Quote
interesting, what kind of applications are you thinking about that involves wireless combined with a RTC?

What can you think of that needs wireless and couldn't have a RTC :D

I use RTCs all the time - knowing the time is just handy.
Title: Re: PICOBEE
Post by: jluciani on Mar 27, 2011, 07:05 pm
Quote
What can you think of that needs wireless and couldn't have a RTC smiley-grin


I agree  ;)



Are the two that come immediately to mind.


(* jcl *)
Title: Re: PICOBEE
Post by: jluciani on Apr 18, 2011, 03:00 am
The PICOBEE datasheet with schematic, BOM and assembly instructions is at

http://wiblocks.luciani.org/PICO/PICOBEE-index.html

I will have a couple of software examples posted in the next few weeks.

(* jcl *)
Title: Re: PICOBEE
Post by: retrolefty on Apr 18, 2011, 03:10 am
Why run the 328 at 12mhz rather then the arduino standard of 16mhz?

Lefty



Title: Re: PICOBEE
Post by: jluciani on Apr 18, 2011, 03:12 am
This board is a 3.3V board. The maximum specified frequency in the datasheet for 3.3V is around 13MHz
so I chose 12MHz.

(* jcl *)
Title: Re: PICOBEE
Post by: retrolefty on Apr 18, 2011, 03:21 am

This board is a 3.3V board. The maximum specified frequency in the datasheet for 3.3V is around 13MHz
so I chose 12MHz.

(* jcl *)


OK, that makes sense. Although some vendors 'stretch' those specs and run boards at 3.3vdc and 16mhz and report no problems. I however certainly do not endorse doing that, just seen it done by Seeeduino and a few other clone vendors.

Lefty
Title: Re: PICOBEE
Post by: frank26080115 on Apr 18, 2011, 04:44 am


OK, that makes sense. Although some vendors 'stretch' those specs and run boards at 3.3vdc and 16mhz and report no problems. I however certainly do not endorse doing that, just seen it done by Seeeduino and a few other clone vendors.

Lefty


That's one of those features where there's really nothing to lose from a features point of view. If it works, great. If it doesn't, "meh, here's why it doesn't work, but you can burn fuses to use 8 MHz instead".
Title: Re: PICOBEE
Post by: Coding Badly on Apr 18, 2011, 10:10 am

You assume that an overclocked processor will fail early (during development versus seven months after installation) and in a way that is easy to debug.  I have found neither of these to be true.

A general rule of thumb is that a bug costs $1 to fix during design, $10 to fix during development, $100 to fix while debugging, and $1000 to fix after deployment.  In my opinion, except for experimental purposes, overclocked processors are never worth the risk (potential failure after deployment).
Title: Re: PICOBEE
Post by: 48X24X48X on Apr 18, 2011, 02:28 pm
Usually things go wrong when multiple factors come into the picture. For example, exposure to temperature and heat over long period of time.I would never try to deploy something by over clocking them. If you need something faster, get a bigger processor.
Title: Re: PICOBEE
Post by: jluciani on Jun 11, 2011, 01:50 pm
Added a wireless temperature logging sketch for K-type thermocouples.
The schematic and example sketch are at http://wiblocks.luciani.org/docs/app-notes/picobee-tc.html (http://wiblocks.luciani.org/docs/app-notes/picobee-tc.html)
I hope to have a library for the MAX31855 done in the next month or so.

Here is a picture of the prototype hardware --

(http://wiblocks.luciani.org/docs/app-notes/images/picobee-tc_top_384x256.jpg)

(* jcl *)