Other Parts Discussed in Thread: CC2530, CC-DEBUGGER
Hello,
I have a CC2530 programmed with the ZNP firmware and it talks well with the application processor. However I have walked into problems with the transmission/reception of signals on the radio. The board follows the reference design of the ZNP mini kit dongles.
Initially, I tried to let the device join an existing network. And the ZNP wouldn't ever return back a state to say it has joined the network. Incase it was a programming issue, the board was programmed to act as a coordinator and tried to let our ZNP-mini kit dev boards join. But they couldn't seem to join successfully either. Which brings me to think that there is an issue of the radio on our board.
Using the smartRF Studio 7 tool and the CC-Debugger I got my board to send out packets/beacons. Whilst it was broadcasting, I probed a pin on the input/zigbee chip side of the balun. I could see a pulse on each transmission, a fraction of a millisecond. This pulse goes from 0v to 750mV. I can also pick up some pulsed noise too, In the range of 50mV pk-pk. My scope also goes upto 350Mhz. So It is hard to tell what frequency it could be at.
I did the same test on the ZNP mini kit dongles. They appear to do the same pulse going up to 1V. But with pulses of noise/data similiar to what I saw on my board. In this instance it had a pk-pk value of 700mV. This noise/data is much more pronounced and also occurs when the ZNP chip is reset and not given any commands to register onto any network.
It may be a mismatch issue, but I haven't worked with 2.4Ghz before and may be making simple mistakes.
Is there anything else that can be done to help diagnose the problem? The board follows the design on the ZNP mini kit, but the layout is altered. Is there anything critical/important that I may have got wrong? Such as track lengths, thickness's. The board using the wrong amount of copper.
Thanks for your time,
Lee.