DW3000 PLL Calibration Process

Wireless Connectivity Ultra-Wideband
1

Hi everyone,

I am trying to calibrate the internal CELL of DW3000. I saw in section 10.4 of its user manual the process of calibration. I follow these stpes, but the PLL does not get locked after calibration. I do the following steps:

  1. Set device in state IDLE_RC: reset AINTIT2IDLE, set FORCE2INIT, establish SYSCLK to 3, clearing FORCE2INIT, restoring SYSCLK to 0.
  2. Set CAL_EN in PLL_CAL register and set AINTIT2IDLE.
  3. Wait until PLL is locked. But it does not happen.

Is there any other step before waiting for PLL to get locked?

2

That part works as documented for me. What happens when you take those steps?

3

I’m waiting for the PLL to lock, but it does not happen. I’m not using the pre-build library
I write and read registers directly.

4

You’re pretty confident in your register read write logic?

You can compare with my code: gadget_play/dw3k.cpp at edd54dfb1af32f78f74877a8ff2b206ed83b0dbd · egnor/gadget_play · GitHub (and gadget_play/dw3k.cpp at edd54dfb1af32f78f74877a8ff2b206ed83b0dbd · egnor/gadget_play · GitHub).

One difference is that I do this straight out of reset so don’t have to force it back into INIT_RC.

– egnor

5

Yes, I’m pretty confident, until now I was capable of doing ranging measurements. I will check your code and see if there are any differences

Thank you.

6

It works correctly!!! It was my fault, when I retry to force it back into INIT_RC. But my measures, do not improve too much.
Thanks!!!