JTAG header highway robbery

Nothing. :-)

I mean it is just not on the BOM for high volumes and software developer can solder it themself if they need it for debuging.

Olaf

On a sunny day (Thu, 14 Feb 2019 11:33:34 -0500) it happened Phil Hobbs wrote in :

I bought some .1 inch IC socket strips, breakable, and use those for all test connectors:

It's the little JTAG, not the big one.

Looks like I can just put a resistor in series with !RESET and it'll survive being installed backwards, so I can probably just use an unshrouded header.

Cheers

Phil Hobbs

Phil Hobbs wrote in news: snipped-for-privacy@electrooptical.net:

So, it is a surface mounted and shrouded header?

I am sure there are several folks making them Go to google images.

Not just google. Search: "jtag header" (less quotes) and a bunch pop up and many with prices. I saw $0.69 each on one.

torsdag den 14. februar 2019 kl. 17.33.44 UTC+1 skrev Phil Hobbs:

don't mount it just make a bed of nails instead?

will a standard 1.27 header fit?

We just have a footprint so only PCB area cost

The connector is called TagConnect

TagConnect also comes with hooks for self sustained connection to the board

SAMTEC FTSH-105-01-L-D-K 2x5 $1.70

MOLEX 87831-1419 2x7 $0.62

There is a pogo sort of thing that pushes onto a pattern of plated-through holes, for free JTAG.

Some of our little ARM chips have to be programmed after they are soldered to the board.

Of course, but this happens on the production test systems with needles.

Olaf

so make a pcb with some pogo pins

Doesn't work for our volumes.

Yeah, we can do that, assuming there's a resistor to prevent a hard short from !RESET to +3.3V, which is what happens when you put the connector on the wrong way.

Since the Samtec one got itself written into the JTAG spec, they apparently have a license to coin money. I was hoping for a knockoff with the same footprint and key geometry.

Cheers

Phil Hobbs

Cute idea, thanks. Something like that might work fine, except that we need at least 9 pins.

Cheers

Phil Hobbs

Phil Hobbs

I guess we could, but our products are fairly expensive so the cost of the header is in the noise. It would be a minor project to set up a few pogo systems, and we'd have to change a lot of board layouts.

The Samtec ones are much much smaller (1.27 mm).

Cheers

Phil Hobbs

torsdag den 14. februar 2019 kl. 21.17.03 UTC+1 skrev John Larkin:

the pins can hit the existing layout

or the crazy, an one edge connector,

something like mini PCI-E is very small, if you only use part of it

For the Coresight debug header (10x2) looks like a 3M 30320-5002HB on my last couple of boards. 0.80 USD in 100's. No shroud.

--Spehro Pefhany