A quick question about SWD vs JTAG…is there a functionality difference between the TMS/TCK/TDI/TDO/TRST JTAG interface and the SWDIO/SWCLK SWD interface? More detail: I used the programmer shield with a Blackmagic Probe and it worked great. Then I got out the breadboard and only connected 3.3, RST,…

I’m don’t think so as SWD is to exactly do what you noticed which is to save pins. But that said, there might be some other implications so let’s see what others have to say :smiley:

Thanks for the feedback. I’ve not run into any issues using it, and it looks like someone has made a user-friendly way to activate this that has been/will be rolled into the firmware. https://github.com/spark/core-firmware/pull/337

Just to save others from clicking back-and-forth with github, see this topic for details: [image] Update: JTAG and SWD programming and debugging from Netbeans! ** Update ** I have something working now, see 3 posts down. I have removed most of this starting posts as it …

I’ve not found any limitations in using SWD in 6 months of debugging. I get the impression that SWD is JTAG re-encoded over a single wire.

Debugging with SWD vs JTAG

Hardware

bko May 15, 2015, 5:48pm 4

Just to save others from clicking back-and-forth with github, see this topic for details:

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Debugging with SWD vs JTAG

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