Cannot program WT51822-S4AT

[zolotiyeruki]

I'm trying use an nRF51 PDK to upload firmware (or, rather, just confirm that I can upload firmware) to one of these modules: www.wireless-tag.com/.../WT51822-S4AT.html

The target is externally powered, so I've connected it like so: Target Vcc -> P20 Pin 3 (VTG) Target SWDIO -> P20 Pin 4 (SWDIO) Target SWCLK -> P20 Pin 5 (SWCLK) Target GND -> P20 Pin 8 (Gnd Detect)

However, when I try to connect to the target using jlink.exe, I get a timeout error.

I hooked up an oscilloscope to the SWDIO and SWCLK lines (connected to the wires between the nRF51 PDK and the target module), and I see the signals changing, so it appears that at least the SEGGER bit is trying to connect.

I've seen a couple other users work with these modules, but I can't seem to have any success. Does anyone have any insights they could lend?

[endnode]

Oh yes, I've seen that. My advice will sound silly but I've seen dozens of cases in past 4 years solved this way so think about it;)

DK and especially SWD over SEGGER OB is sensitive to noise so probably either your USB cable or wire between DK and target are crap. Or both. Try to rewire and be careful, use proper thick and short cables, same lengths, good solder joints if applicable etc.

[zolotiyeruki]

Wow, I think you're right. I soldered a new device with SW lines only about 1" long, and the recover appears to have worked. Previously, the lines were about 6" long. nRFgo Studio sees the target as well, and can program firmware to it also. Thank you!