SPWF01SA - issue with SCAN command

Posted on August 13, 2015 at 14:36

Hey,

I have a peculiar problem, one I didn't have before, and I am not sure how exactly I have produced it...

I was refactoring my code, in which I am asking the module to start scanning for networks immediately upon the module initialization...

To be more precise, I am waiting for the detection of WIND:0 and WIND:32 messages, and afterwards I send AT+S.SCAN<CR> command.

Here's the thing: the module freezes. It stops being responsive to any command whatsoever the moment I send this SCAN command.

Now, if I put the delay of ~5ms after the detection of above-mentioned WIND messages and before sending the SCAN command, it works well.

Here's the complete procedure flow:

(1) pull reset pin down ( to reset the module at the beginning)

(2) wait 5ms

(3) pull reset pin up

(4) wait for WIND:0 and WIND:32 messages

(5) (optionally) wait for additional 5ms

(6) send AT+S.SCAN<CR>

With (5) it works, without (5), it doesn't, the module stops responding completely.

I have no problem with the insertion of this delay, but I was wondering what could be the issue here. If something crosses your mind, please do share, so I can improve the library.

The firmware version is 141106-0950875-SPWF01S.

Thanks!

M.

#spwf01sa-wifi-scan-command