nRF51822 Advertising works, connecting doesnt

[Philippe]

Hi everybody

I've got a problem with my "custom hardware" with the "nRF51822 QFAAFA 1322AA" MC by Nordic. When I try to connect the hardware with the "Master Control Panel" I can see the advertising. When I try to connect the hardware and read the data the connection is going to loose the link (see the screenshot bleerror in the Attachments). The second screenshot ("ble error.png" ) shows the traffic log with a TI sniffer when i try to connect the hardware with the Master Control Panel. As you can see the Master gets no acknowledge, that means that my custom board isn't able to receive.

I've read a lot of articles in this forum and saw that the 16 MHz crystal may be a problem. I'm using a 16 MHz crystal by AVX (www.farnell.com/.../84480.pdf) with two 12 pF capacitors as "load capacitors". Do you think this crystal may be the problem? Or did anyone have a similar problem and get a solution? Im using the SDK 4.4.2 and softdevice 5.2.1.

Thank you for your answers!

bleerror.PNG

[Asbjørn]

What about the 32 kHz source? Are you using an external one or are you basing the operation on the internal RC oscillator? If you're using an external, could you try switching to setup to use the internal RC just for the purpose of testing?

[Philippe]

I'm using an external one, but it's the same setup as Nordic has with the same oscillator. But thank you for your hint, I'll try it with the internal one and give you a feedback ;).