How to turn OFF WiFi Accesspoint on Olimex ESP32-EVB

[ikeaTheMan]

My BSB-LAN ist running on an Olimex ESP32-EVB via LAN. But it still opens an WiFi-Accesspoint (SSID is something like "ESP32_666FA3"). I want to turn WiFi completely off, but I can't find a setting for that on the Web-Gui. I tried to turn on "Energiesparmodus" but that did not help.
So... how can I turn WiFi completely off?

[fredlcore]

It only creates an access point if the network connection fails otherwise, for example you set up a LAN connection, but there is no LAN connected or it got disconnected or cannot connect to WiFi. This is to prevent users from locking out from their system and saves me a lot of troubleshooting times. It stays active for 30 minutes only, then the device reboots and retries to connect regularly again. Based on the other potential security risks that come along with microcontrollers like the ESP32 (see our Wiki), this is negligible and thus is a feature, not a bug.

[ikeaTheMan]

Thanks a lot for your reply. But the Olimex ESP32-EVB has a valid connection via LAN (I can see that in my FritzBox, and I can reach it via the LAN-IP). But everytime I get close to the ESP I see the AP on my smartphone. The AP seems to be continiously on, although it's connected via LAN.

[fredlcore]

That shouldn't be the case. If you look at the code, it only establishes the AP if the ESP32 does not have any other connection anymore. Please post a Serial Monitor log right from boot-up. If the AP is set up, it'll print a message with the according information. Then we can see under which condition it is set up.

[ikeaTheMan]

I am back again with some details:

When bboting BSB-LAN on Olimex ESP-EVB it connects via LAN, no AP is visible.
When unplugging the LAN cable, the AP starts and becomes visible (see commented logs below).
After plugging in the cable again, ETH connects and the logs say

Ethernet connected.
Temporary AP 'BSB-LAN' deactivated.
Ethernet got IP: 192.168.69.8
Connecting to MQTT broker 192.168.69.37 on port 1883...

But the AP stays visible for hours (and probably forever), and I am able to connect to it with my smartphone.

READY
Reading EEPROM
0
1
2
3
4
5
6
…
53
54
55
56
Reading done.
EEPROM schema v.14 Program schema v.14
Address EEPROM option 0: 0
Address EEPROM option 1: 1
Address EEPROM option 2: 3
...
Address EEPROM option 57: 2044
Size of cmdtbl: 37128
free RAM: 283360
BSB-LAN version: 4.2.19-20241119205640
Microcontroller: ESP32_EVB
Using RX/TX pins 36, 17
Bus type defined in config: BSB
E (218) uart: tout_thresh = 2 > maximum value = 1
ESP Arduino version: 3.0.7
E (229) uart: tout_thresh = 2 > maximum value = 1
E (229) uart: tout_thresh = 2 > maximum value = 1
Power-saving activated.
Init One Wire bus...
numSensors: 4
PPS settings:
Starting network connection via Ethernet/LAN...
Ethernet Started.
Ethernet connected.
Ethernet got IP: 192.168.69.8
IP: 192.168.69.8 netmask: 255.255.255.0 gateway: 192.168.69.1
Waiting 3 seconds to give Ethernet shield time to get ready...
Trying to get NTP time...
Date and time acquired: 30.10.25 12:59:05
Device family: 163
Device variant: 5
Start network services
Starting MDNS service with hostname BSB-LAN
Setup complete

### MQTT publishing … ###
### unplugging LAN cable: ###

Virtual parameter 20300.1 queried. Table line 1306
Publishing to topic: BSB-LAN/0/44/20300.1/status
Payload: 25.00
Successfully published...
Ethernet disconnected.
Setting up AP 'BSB-LAN'
IP address of BSB-LAN: 192.168.4.1
Connect to access point 'BSB-LAN' with password 'BSB-LPB-PPS-LAN' and open the IP address.
Ethernet disconnected.
MQTT connection lost
Temporary AP 'BSB-LAN' deactivated.
Setting up AP 'BSB-LAN'
HEIZ->EM1 INF      0504024E 02 00 00 04 15 04 00 00 00 00 00 00 00 00 00 00
DC 80 03 1B 02 05 04 02 4E 02 00 00 04 15 04 00 00 00 00 00 00 00 00 00 00 29 69
IP address of BSB-LAN: 192.168.4.1
Connect to access point 'BSB-LAN' with password 'BSB-LPB-PPS-LAN' and open the IP address.
HEIZ->EM1 INF      0504024E 02 00 00 04 12 34 00 00 00 00 00 00 00 00 00 00
DC 80 03 1B 02 05 04 02 4E 02 00 00 04 12 34 00 00 00 00 00 00 00 00 00 00 DE 65
DSP1->HEIZ QUR 8310.0 Diagnose Erzeuger - Kesseltemperatur-Istwert: 
DC 8A 00 0B 06 3D 0D 05 19 4F 8C
HEIZ->DSP1 ANS 8310.0 Diagnose Erzeuger - Kesseltemperatur-Istwert: 40.3 °C
DC 80 0A 0E 07 0D 3D 05 19 00 0A 16 22 B7
. . . . . . . 
### plugging in the LAN cable again: ###
HEIZ->EM1 INF      0504024E 02 00 00 04 1E 46 00 00 00 00 00 00 00 00 00 00
DC 80 03 1B 02 05 04 02 4E 02 00 00 04 1E 46 00 00 00 00 00 00 00 00 00 00 D3 38
Ethernet connected.
Temporary AP 'BSB-LAN' deactivated.
Ethernet got IP: 192.168.69.8
Connecting to MQTT broker 192.168.69.37 on port 1983...
Client ID: BSB-LAN
Will topic: BSB-LAN/status
Failed to connect to MQTT broker, retrying...
LAN->HEIZ QUR 700.0 Heizkreis 1 - Betriebsart: 
DC C2 00 0B 06 3D 2D 05 74 9C 4B
HEIZ->LAN ANS 700.0 Heizkreis 1 - Betriebsart: 0 - Schutzbetrieb
DC 80 42 0D 07 2D 3D 05 74 00 00 B7 73
#700: 0 - Schutzbetrieb
Publishing to topic: BSB-LAN/0/9/700/status
Not connected to MQTT broker.
LAN->HEIZ QUR 812.0 Heizkreis 1 - Vorlauffrostschutz Heizkreis 1: 
DC C2 00 0B 06 3D 21 11 81 99 27
HEIZ->LAN ANS 812.0 Heizkreis 1 - Vorlauffrostschutz Heizkreis 1: 1 - Ein
DC 80 42 0D 07 21 3D 11 81 00 FF 7B 94
#812: 1 - Ein
Publishing to topic: BSB-LAN/0/9/812/status
Not connected to MQTT broker.
LAN->HEIZ QUR 1000.0 Heizkreis 2 - Betriebsart: 
DC C2 00 0B 06 3D 2E 05 74 C5 1B
HEIZ->LAN ANS 1000.0 Heizkreis 2 - Betriebsart: 0 - Schutzbetrieb
DC 80 42 0D 07 2E 3D 05 74 00 00 79 93
#1000: 0 - Schutzbetrieb

### after a while mqtt broker connects again ###

EM1->HEIZ INF      05000253 00 00 00 61 00 00 00
DC 83 00 12 02 05 00 02 53 00 00 00 61 00 00 00 78 B5
Connecting to MQTT broker 192.168.69.37 on port 1883...
Client ID: BSB-LAN
Will topic: BSB-LAN/status
Connected to MQTT broker, updating will topic
Subscribed to topic 'BSB-LAN/#'
Published status 'online' to topic 'BSB-LAN/status'
LAN->HEIZ QUR 700.0 Heizkreis 1 - Betriebsart: 
DC C2 00 0B 06 3D 2D 05 74 9C 4B
HEIZ->LAN ANS 700.0 Heizkreis 1 - Betriebsart: 0 - Schutzbetrieb
DC 80 42 0D 07 2D 3D 05 74 00 00 B7 73
#700: 0 - Schutzbetrieb
Publishing to topic: BSB-LAN/0/9/700/status
Payload: 0 - Schutzbetrieb
Successfully published…

### AP stays visible / on ###

When connecting to this AP, I get 192.168.4.2 as ip-address via its DHCP and I can access BSB-LAN WebGUI via 192.168.4.1

[fredlcore]

Ok, please look at this function in BSB-LAN:

void removeTemporaryAP() {
#if defined (ESP32)
//  esp_wifi_disconnect(); // W.Bra. 04.03.23 mandatory because of interrupts of AP; replaces WiFi.disconnect(x, y) - no arguments necessary
  WiFi.softAPdisconnect(false);
  localAP = false;
//  WiFi.enableAP(false);
  printlnToDebug("Temporary AP 'BSB-LAN' deactivated.");
#endif
}

WiFi.softAPdisconnect(false); should disable the local AP. If it doesn't (do that anymore), then there's an issue with this built-in ESP32 function and nothing I can fix. But if there is another way how to turn off the SoftAP, then please let me know.

[ikeaTheMan]

Another obtrusiveness is, that the AP is not named "BSB-LAN" but "ESP_666EA5". And it is open / not protected by any password.

[fredlcore]

Ok, can you try and change the function to this one:

void removeTemporaryAP() {
#if defined (ESP32)
  WiFi.softAPdisconnect(true);
  WiFi.mode(WIFI_OFF);
  localAP = false;
  printlnToDebug("Temporary AP 'BSB-LAN' deactivated.");
#endif
}

If it works, and the AP disappears, please try again to reconnect and see if it comes back (as it should). Do that a few times to check that the mechanism works. Thanks!

[ikeaTheMan]

I did not yet reflash the board, but I found out: by switching the state of "Energiesparmodus" (no matter form OFF to ON or vice versa) -> the AP turns off. One day I'll reflash the board with your fix, I'll report results here.

[fredlcore]

Well, it would be nice to test out the potential solution that you asked for, and not give the impression that I do my support here for nothing. "One day" sounds a bit like "sometime"...

[ikeaTheMan]

Today is "one day". It seems to fix the issue. Even the AP has the correct name "BSB-LAN" now instead of "ESP_666EA5". Thanks a lot for your precious time and support.

[fredlcore]

Thanks, then I'll commit the changes.