How to use Access point mode?

General
1

I would like to use the web server function in access point mode.
I’ve created a secrets.json file containing:

{
    "wifi_ssid": "YOUR_WIFI_SSID",
    "wifi_password": "YOUR_WIFI_PASSWORD",
    "robot_id": 1,
    "ap_ssid": "XRP {robot_id}",
    "ap_password": "remote.xrp"
}

I am running the webserver_example.py example code.
I have two WiFi connections on my laptop. I leave one of the connected to the internet and the other one I connect to XRP 1 (using the password in the secrets.json)

When the code runs, it displays:

MicroPython v1.20.0 on 2023-04-26; Raspberry Pi Pico W with RP2040
Type "help()" for more information.
>>> 
OK2021-01-01 00:46:15 [info     / 117kB] Starting Access Point "XRP 1"
2021-01-01 00:46:15 [info     / 105kB] Starting DNS Server at 192.168.4.1
2021-01-01 00:46:15 [info     /  96kB] > starting catch all dns server on port 53

Now what?
If I open a tab in Chrome and enter the address 192.168.4.1 is says page cannot be found. How do I get the web server page to display?

2

In my original post, I was using the XRP at the school where our FRC team meets.

I took the XRP home to see if I got a different response.
At home, the computer I’m using is hard wired ethernet to the internet. However it also has a wifi adapter.
I ran the same sample software, connected to the XRP via WiFi and upon doing so, a tab automatically opened in Chrome at this address:
https://www.msn.com/?ocid=wispr&pc=u477

But now if I type in 192.168.4.1 into the URL, I finally get the web page to control the XRP!

So there’s something at the school that seems to be blocking me from using the XRP in webserver access point mode.

And I’m not sure why the MSN page appeared since it’s not the default URL which opening a new tab is supposed to go to.

Any suggestions? I have no expertise in networking. In theory I could have our teacher ask the IT department about why it’s being blocked but I don’t even know what to ask at this point.

I have a sneaking suspicion that this is the same problem I have in trying to use Java/WPILIB on the XRP at the school which I posted about here:

I really need to find a solution to this because the whole reason we bought the XRPs was to teach robot programming to our FRC team :frowning_face:

3

I have not used a laptop that has two wifi connections at the same time, but don’t see why that wouldn’t work. You may want to try with just the one connected to the XRP. But, everything you have posted makes me feel like there is a WiFi blocker turned on in your school. We have seen this with many schools.

4

I did try disconnecting from the 2nd wifi but it didn’t work :frowning:

If I were to ask the school IT department to stop whatever it is that they are doing, what would I ask? What is it that we need to have in order for this to work?
If I ask for something specific, there’s a (remote) chance we might get them to allow it. But I don’t know what I’m asking for.

Is there any other workaround you can think of that would enable us to communicate with the XRP wirelessly?

5

When we do a FIRST event we usually bring all of our equipment set up in a way that we know works outside of the school and then sit down with the IT people to figure out why it doesn’t work inside their walls. You may also want to walk a few feet outside of the school with your laptop and XRP and see if it works. Then you can tell them that it works right outside the school and stops when you enter the school. This tends to help an IT person realize that it is something with their setup.

6

Do you know if it would be possible to set up our own LAN? If we were to bring in a router could we access the XRP through that? If so, how would we set that up?
Or would we likely still have interference? My apologies if these are dumb questions but I know very little about networking.

7

Probably not. The reason schools turn on WiFi blockers is that they don’t want someone setting up a hotspot or a router with a hotspot device that would then let a group of people access anywhere on the internet. The WiFi blocker makes it so that the WiFi IT is providing is the only one that will work. They can let individual approved devices through if they have the MAC address of each specific device. Or, they could just turn the WiFi blocker off.

8

I found a solution!
I bought an old router (Linksys WRT54G). Reset it to factory defaults. Set up an SSID with WPA PSK passkey. I did not connect this router to the internet.

On the XRP, in the secrets.json file I put the routers SSID/passkey into the wifi_ssid and wifi_password fields.

On my laptop I have 2 wifi connections. One is connected to the school WiFi. The other I connect to the router SSID.

And now it works. So basically I’m using the XRP in Bridge mode as described in the documentation.

1 Like
9

Fantastic, lesson learned. Thank you for the persistence and sharing.

1 Like
10

I was too optimistic. This worked for a while. And then it stopped working and I could not get it functional again. I will be speaking to one of the school network “experts” on Monday. Any suggestions on what I should tell him or ask him?