Trouble waking up from low power listening mode

I am using 2 DWM1001-Dev boards and attempting to use the low power listening mode to send messages back and forth between the two. Using the DW1000 driver examples 8a and 8b, I have a system working. However it appears that when the low power listening mode is enabled, the dwt_initialise routine fails when the board is reset and even completely disconnected from power and reconnected. Specifically the dwt_readdevid routine is returning zeros indicating SPI communication is not working.

After beating my head against a wall for a couple days, I decided to place the dwt_initialise routine inside of a loop at the top of my main. This seems to be a usable workaround for now. This brute force method of calling dwt_initialise seems to work after several failed calls.

Any idea why this is happening? Its like the DW1000 is stuck in low power listening mode, even when the board is reset. I am holding the RST pin low for 2ms before calling dwt_initialise to reset the DW1000. The only thing I can think of is that VDD_AON is still powered on the DW1000 for some reason, thus all of the chip configuration is reloaded and the DW1000 goes directly to sleep. Is it possible with this dev board that on board capacitors will continue to supply VDD_AON for some time?



Hi Karl,
This would be expected behaviour , see note 9 on the bottom of 8a.
You are only expected to use the device in LPL when you will wake it with good frame reception.
See also IC user manual section 4.4