Comments on: Meet the JeeSMD kit

By: bstoke

bstoke — Thu, 18 Mar 2010 23:26:58 +0000

my point is I think this thing is actually Revolutionary when combined with the Ports library and Plugs.

But I cant build one to save my life.

By: jcw

jcw — Thu, 18 Mar 2010 23:11:17 +0000

That’s why there’s the JeeNode / JeeNode NoRF / JeeNode USB … http://news.jeelabs.org/docs/

By: bstoke

bstoke — Thu, 18 Mar 2010 23:05:32 +0000

Sorry, most of (me) us cant do SMD soldering.

I could solder the headers on, and that is one great Arduino (ish) kit in my opinion.

but I dont have SMD soldering sorted.

By: PaulH

PaulH — Thu, 18 Mar 2010 10:13:58 +0000

Whoops must have missed that… Thought I had read most of the blog posts. Following this project with interest. Great work!

By: jcw

jcw — Thu, 18 Mar 2010 09:23:00 +0000

Yes – I’m aware of that – http://news.jeelabs.org/2009/02/27/out-of-spec/

So far, I haven’t ever seen it cause problems – as you point out. I don’t know whether the clock itself is an issue, or circuits further down the line. In the latter case, one could run the units at a lower frequency using the system clock pre-scaler, e.g. when used in a wider temperature range.

By: PaulH

PaulH — Thu, 18 Mar 2010 09:17:40 +0000

It will probably never be an issue but at 16MHz and 3.3V you are overclocking the MCU according to the datasheet (see the Speed Grades section in DC characteristics).

By: jcw

jcw — Thu, 18 Mar 2010 00:23:35 +0000

Good point. Or forego the headers altogether. I agree that with something as small as this, headers are starting to take up a relatively large amount of space/height. For me, the main use will be "deeply embedded" (and permanent), maybe even soldering some plugs directly to the ports with short pieces of wire. Without headers, you can builds some pretty flat (or tightly-sandwiched) units.

That's also why I'm considering including only the PWR/SER/I2C and ISP/SPI headers in the kit.Enough to get going, but leaving all the options open w.r.t. the port headers.

By: FlorinC

FlorinC — Thu, 18 Mar 2010 00:00:10 +0000

To reduce the height clearance, you could use machined (round) headers. I found them much better even from the electrical (contact) standpoint. See my post here: http://timewitharduino.blogspot.com/2010/01/what-difference.html.