WiFi Scan Example not working--No ACK, R00

I followed all the instructions in the Network and Wifi wiki and downloaded and included all the libraries.

However when I go to run the Wifi Scan example it just prints the following to the Serial monitor.

Scrolled through the serial monitor output and also found these messages:

16:10:03.119 -> No ACK, R00
16:10:03.119 -> scan start
16:10:03.119 -> scan doneNo ACK, R00
16:10:03.119 ->
16:10:03.119 -> -1 networks found[E][esp_event_loop.c:99] at_unified_cb(): at_unified evt: 4
16:10:03.119 ->
16:10:03.119 -> No ACK, R00
16:10:03.119 -> No ACK, R00
16:10:03.119 ->
16:10:03.119 ->
16:10:03.119 -> No ACK, R00
16:10:03.119 -> No ACK, R00
16:10:03.119 -> No ACK, R00
16:10:03.119 -> No ACK, R00
16:10:03.152 -> No ACK, R00

16:10:09.152 -> No ACK, R00
16:10:09.152 -> [E][esp_event_loop.c:99] at_unified_cb(): at_unified evt: 4
16:10:09.152 ->
16:10:09.152 -> No ACK, R00
16:10:09.152 -> No ACK, R00

16:10:10.134 -> No ACK, R00
16:10:10.134 -> No ACK, R00
16:10:10.134 -> [E][esp_event_loop.c:99] at_unified_cb(): at_unified evt: 4
16:10:10.134 ->
16:10:10.134 -> No ACK, R00
16:10:10.134 -> No ACK, R00
16:10:10.134 -> No ACK, R00

Two questions:

  1. Did you update the firmware on RTL8720? The wiki specifically states you must do this first: https://wiki.seeedstudio.com/Wio-Terminal-Network-Overview/

  2. Sometimes WIFI routers are configured to not broadcast their SSID. Is it possible your router is not broadcasting the SSID?

Hey Dennis_Mabrey,

  1. Yes that was the first thing I did. I followed the instructions in the wiki. I suppose I could have done it wrong but it seemed like everything was correct during the process.
  2. I can see the SSID on my phone so as far as I know it is not hidden.

Unsure what the problem is but I would try the next example in the Wiki that connects directly to the network by giving the SSID and the network password.

If that doesn’t work then I don’t know what to tell you.

Hi @ZebraWolf

It does seem like it’s the WiFi firmware is not uploaded properly to me. Can you re-upload the firmware to the WiFi Core again please. It should say successful if done correctly.

Well it looks like I goofed when doing the firmware install. I believe now after going through it a second time that I forgot to do the “erase” step before doing the download. Now the wifi scan is working perfectly.

Thank you Dennis_Mabrey and ansonhe97 for the help!

2 Likes

Glad to hear it is now working.

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