Connecting jlink lite with nrf51822

[David]

Hi,

I have 2 questions regarding this topic:

1. Which specific J-Link lite mode do we get from nrf51822 Development Kit? Is it the 9 pins model or 19 pins model?

2.Rather than trying to explain the question, I drew the question instead(pardon for my bad drawing on MS paint). Essentially, since pin 23 of nRF51822 acts as SWDIO/nRESET, should I connect pin 23 to SWDIO or nRESET of the J-Link lite programmer? If I choose one, what about the other pin on that programmer board?

[Ole Morten]

Have you seen this? It seems to cover what you need.

[David]

Ah, my bad for not finding that thread first :/

From seeing that post, I can definitely find the answer for my first question.

However, in regard to my second question, I'm not entirely sure if the image you posted in that thread suggests that I should leave the nRESET pin on J-LINK lite unconnected to anything, or if that pin was left unconnected for a reason unknown to me.

Also (sorry for an additional question), by looking at J-LINK LITE datasheet (http://www.segger.com/cms/admin/uploads/productDocs/UM08001_JLink.pdf), I believe that SWDIO should have pull up resistor and SWDCLK should have pull down resistor. However, does nRF51822 already have those pull up and pull down resistors internally for SWDIO and SWDCLK? I seem to remember seeing them somewhere, but I can't remember where the information is located at, so I'm not exactly sure.

[Ole Morten]

Yes, you can leave the reset pin of the J-Link Lite unconnected, and second revision nRF51822 have all needed pull-up and pull-downs internally. I'd recommend you to take a look on the schematics for the Development Kit, which shows exactly how this can be done: https://www.nordicsemi.com/eng/content/download/13247/213200/file/nRF51822%20Development%20Kit%20-%20Hardware%20files%202_0.zip

[David]

Ah, thanks for clearing up my doubt :)

Unfortunately, I can't seem to open that link, the website says that I don't have permission to access this file/area.

[Jay Tyzzer]

Hello David,

If you need access to the Evaluation Kit design files please contact me directly via email.

jay.tyzzer(AT)nordicsemi.no

Thanks,

Jay Tyzzer