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From: Nial Stewart on 14 May 2010 04:53
> Some of the newer ARM devkits we've been using lately have come with 2x5 0.05" through hole
> instead. 75% of your surface area back is a pretty decent victory.


Rob, 1.27mm pitch sounds a bit flimsy but if ARM are using them for
programming headers they must be happy enough with reliability and
robustness.

Do they use a shrouded part?

You wouldn't have a part number would you (or an ARM kit number), as usual
Digikey has too many options.


Nial.



From: Nial Stewart on 14 May 2010 04:54
"Thomas Entner" <thomas.entner(a)entner-electronics.com> wrote in message
news:25e512b7-8076-495a-b1ee-95e080e01ff5(a)k17g2000yqf.googlegroups.com...
> With our EEBlaster (http://www.entner-electronics.com/tl/index.php/
> eeblaster.html), we support a 2x3 2mm pitch header which uses just
> about 1/3 of the area of the 2x5 header. We think this is a good
> compromise of size, price, reliability and availability. We have the
> pinout made public on the mentioned link, so everyone can use it,
> either together with our EEBlaster or with a self-made adapter-cable.
> Best regards
> Thomas Entner
> www.entner-electronics.com


That certainly looks a good option Thomas, top of the contenders so far!


Nial.


From: Nial Stewart on 14 May 2010 05:00
> I use a 2x4 pin 2mm header for JTAG programming of Xilinx CPLDs. This seems to work quite well,
> but maybe for chipscope or similar testing, you need a couple more pins.
> Jon

Jon,


I think for Altera's SignalTap you only need the JTAG signals so Thomas
has pipped you with a 2x3mm header rather than 2x4mm header!


Nial


From: Rob Gaddi on 14 May 2010 12:46
On 5/14/2010 1:53 AM, Nial Stewart wrote:
>> Some of the newer ARM devkits we've been using lately have come with 2x5 0.05" through hole
>> instead. 75% of your surface area back is a pretty decent victory.
>
>
> Rob, 1.27mm pitch sounds a bit flimsy but if ARM are using them for
> programming headers they must be happy enough with reliability and
> robustness.
>
> Do they use a shrouded part?
>
> You wouldn't have a part number would you (or an ARM kit number), as usual
> Digikey has too many options.
>
>
> Nial.
>

We're just trying this plan out on our boards for the first time, so
I'll have to let you know how it turns out. This time we're using an
unshrouded connector, since we've got giant DC/DC converters next to
them providing mechanical cover. Digikey part S9015E-05-ND.

--
Rob Gaddi, Highland Technology
Email address is currently out of order
From: whygee on 14 May 2010 13:01
Nial Stewart wrote:
> It would be good to have a more compact 'standard' surface mount programming
> header.
> I've used Molex Picoblade vertical headers and connectors reasonably sucessfully
> but these probably aren't robust enough for high volume operation (it's only
> rated at 30 mating cycles though I've had a lot more out of it).
30 only ? damn...

> Has anyone any better solutions?
I don't know if mine is better but after having used
other programming means than JTAG, I have come to
these conclusions :

- the target should have the female connector,
less likely to be damaged. OTOH, the probe has the
male pins and they can be easily damaged so I plan
interchangeable/disposable headers. It's better
to spend a fraction of dollar on a new probe header
than to fix an existing board :-/

- My next projet will use 2mm or 1.27mm
connectors with the usual 2x5 configuration for JTAG.
No idea which one I'll finally choose.
I'll also make a small adapter for the 2.54mm probe.

- spring-loaded test probes are also great :
they're 10 or 100x more expensive per pin
but there is no part to solder on the target,
no hole to drill or height problem.
Well, it's extreme, right...

- Do never forget to key the connectors !
it is a safe to sacrifice at least one pin to prevent
reverse connexions or shifted connexions.

> Come on Altera (and the rest), give us a standard.
don't count on them to "give" a "good" standard ;-)
they're in for the money, they follow the money...

> Nial.
yg
--
http://ygdes.com / http://yasep.org
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