Treedix 2pcs JTAG Breakout Board Adapter Converter SWD Breakout Jtag Debug Board with 2 Row 1.27mm Pitch 10pins Female to Female IDC Connector Flat Flexible Gray Ribbon Jumper Cable 200mm for J-Link

This is just a breakout board but it does its job.

I am using this with a Segger EDU J-Link. Used the attached image for the connections and it is working as expected. Connected to a Nordic Semi nRF51822.

These were a good, cheap alternative to the overpriced ones on DigiKey. However, the end connectors may have been attached wrong. The wrong signals were going from the programmer to the jtag adapter on my pcb. There’s a notch on the connectors on each side of the cable, so there’s only one way to connect them. I had to cut off the notch on the connector of this cable and rotate it 180 degrees before plugging it into the programmer. That was the only way they worked. Other than that, I’ve had no issues with them.

The listing says it works with Atmel-ICE, but the connectors are not oriented correctly on the ribbon cable for that. You can cut off the tab and insert it the other way round and it's gonna work fine, but come on.

Nice board but their quality control is poor. I spent a decent amount of time trying to figure out why my debug setup wasn't working. Eventually, I looked at the solder joints for the surface mount connect under a microscope and I saw the solder past wasn't melted. I had to carefully hit each pin with the tip of my solder iron to get it to flow. The picture attached is after I made the correction. Make sure you have some rework tools if you buy these and at a min do a continuity test on each pin before using it.