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Is there a good way to load firmware onto a PCB that has a 2x5 arrangement of JTAG headers that doesn't involve soldering on pins every time?

I tried getting come pogo pins in the hopes of being able to jam them into an IDC cable (which the website I bought it from suggested doing), but the pins are clearly larger than the holes they're supposedly supposed to go into.

I can't just touch it with wires, because the connection won't be electrically solid (which is what the pogo pins were for), but I can't think of a better way around this.

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  • \$\begingroup\$ what's wrong with permanently soldering the jtag header in place? \$\endgroup\$ – kjgregory Jul 1 '14 at 17:40
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    \$\begingroup\$ Why do you have to remove the headers? The male part costs pennies, why would you fool with it? \$\endgroup\$ – Spehro Pefhany Jul 1 '14 at 17:59
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    \$\begingroup\$ Have a look at "tag-connect". \$\endgroup\$ – pjc50 Jul 1 '14 at 18:02
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    \$\begingroup\$ Tag Connect rocks. \$\endgroup\$ – Matt Young Jul 1 '14 at 18:59
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    \$\begingroup\$ Here's another vote for Tag-Connect. They have pre-made cables for several programmers. \$\endgroup\$ – tcrosley Jul 1 '14 at 22:49
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I am designing a board right now, and I can't leave the JTAG header in place due to height restrictions. I solved the problem by making this custom footprint:

enter image description here

For prototyping, this 1.27mm socket can be soldered into place. For production, this set of pogo pins should mesh with the circular areas.

I haven't tried it yet, but I think I'll put some plated through holes in the center of the circles to help with locating the pogo pin block. The holes would need to be smaller than the pins, of course.

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  • \$\begingroup\$ That's exactly how I usually do it. I got pogo pins that won't pass through the standard holes you would use to install the headers and I just program them using the pogo pins. The problem is that you need to press down with some strength to be able to make contact with all the pins (at least 6) and because of that is the board is held well it might move aside and flip annoyingly. \$\endgroup\$ – user34920 Jul 1 '14 at 19:22
  • \$\begingroup\$ I'll keep this in mind in the future, but for now the boards already exist, and all they have are flat connection pads. \$\endgroup\$ – Ahmed Jul 2 '14 at 14:59
  • \$\begingroup\$ @Ahmed What is the pitch of your jtag header pads? \$\endgroup\$ – bitsmack Jul 2 '14 at 21:52
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I ended up solving this by using a drill bit to ream out the plastic around the header of the IDC cable, and then jamming the pogo pins into the holes.

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