starred/WiFiManager

Fork 0

mirror of https://github.com/tzapu/WiFiManager.git synced 2026-04-27 09:05:56 +03:00

[GH-ISSUE #502] Exception 28: LoadProhibited when running Wifi Scan in Dev-Version #420

New issue

Open

opened 2026-02-28 01:25:12 +03:00 by kerem · 4 comments

kerem commented

2026-02-28 01:25:12 +03:00

Owner

Originally created by @thomsenle on GitHub (Feb 5, 2018).
Original GitHub issue: https://github.com/tzapu/WiFiManager/issues/502

Hey,

very cool to see the development of the wifimanger.
I played around a little with the development version and always get a Exeption 28 when i run the Webportal permanent.

My main loop only consists out of
if (!webportalrunning) { wifiManager.startWebPortal(); webportalrunning = true; } else wifiManager.process();

In the debug i can see that its scans for the networks and then crashes and reboots. Unfortunatly i have no idea where to start searching for the error.

I allready errased the flash totaly as suggested in a other issue. No change for me.

Thanks for your help, Thomas
Please let me know if you need more debug informations for testing.

Debug output:
*WM: Starting Web Portal
*WM: HTTP server started
*WM: <- HTTP Wifi
*WM: Scan done
*WM: DUP AP: FRITZ!Box Fon WLAN 7270
*WM: DUP AP: Vodafone Hotspot
*WM: DUP AP: Vodafone Hotspot
*WM: DUP AP: Vodafone Hotspot
*WM: DUP AP: Vodafone Hotspot
*WM: DUP AP: Vodafone Homespot
*WM: DUP AP: Vodafone Homespot
*WM: DUP AP: Vodafone Homespot
*WM: DUP AP: Vodafone Homespot
*WM: AP: -57 boingboing
*WM: AP: -59 FRITZ!Box Fon WLAN 7270
*WM: AP: -67 Fritzbox-0815
*WM: AP: -67 Hallo Gast! WLAN
*WM: AP: -69 WLAN-B8BAHX
*WM: AP: -69 Telekom_FON
*WM: AP: -80 KabelBox-3760
*WM: AP: -80 Vodafone Hotspot
*WM: AP: -80 Vodafone Homespot
*WM: AP: -82 FRITZ!Box 6490 Cable
*WM: AP: -82 TP-LINK_AC1A06
*WM: AP: -87 NETGEAR88
*WM: AP: -88 KabelBox-364C
*WM: AP: -89 TP-LINK_B732
*WM: AP: -89 HITRON-3420
*WM: AP: -90 gaensebluemchen
*WM: AP: -91 Netzwerk_KW1509
*WM: AP: -92 vdr.fische.leipzig

Stack-Trace:

Exception (28):
epc1=0x402151f0 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000001 depc=0x00000000

ctx: cont
sp: 3fff1080 end: 3fff1450 offset: 01a0

stack>>>
3fff1220: 3fff12f0 00000004 3fff125c 402118c2
3fff1230: 00000001 ff000000 3fff1274 4021179c
3fff1240: 3fff12f0 00000004 3fff0040 4020db1d
3fff1250: 00000000 00000000 00000000 3fff46cc
3fff1260: 0000000f 00000003 3fff6104 40100648
3fff1270: 00001404 3fff47f4 0000005f 00000050
3fff1280: 3fff45fc 0000006f 00000069 33373031
3fff1290: 00001500 3fff1314 3fff1314 402117f7
3fff12a0: ffffffff 0000000c 00000037 ffffffff
3fff12b0: 00000011 00000046 00000060 00000065
3fff12c0: 00000001 00000001 3fff12f0 4010068c
3fff12d0: 00000001 00000001 3fff0040 4020b9ec
3fff12e0: 00000001 00000001 3fff0040 4020ff47
3fff12f0: 3fff4674 0000004f 0000004a 00000000
3fff1300: 00000000 00000000 3fff600c 000000ef
3fff1310: 000000ec 3fff6104 0000155f 00001555
3fff1320: 00000001 00000001 3fff4284 40213664
3fff1330: 00000000 00000000 3fff4284 4020b9e2
3fff1340: 3fff4284 3fff38bc 3fff4284 4020ba1e
3fff1350: 00000000 00000000 00000000 402119a0
3fff1360: 3fff4284 3fff38bc 3fff387c 4020bab1
3fff1370: 3fff47ac 0000000f 00000005 40209f10
3fff1380: 3fff38bc 00000001 3fff0430 3fff38a0
3fff1390: 00000001 00000000 0000000f 3fff4284
3fff13a0: 00000000 00000000 3fff387c 3fff041c
3fff13b0: 00000001 3fff38a0 3fff387c 4020bd10
3fff13c0: 3fffdad0 00000000 3fff35ec 4020ad3d
3fff13d0: 00000000 3fff4774 40212338 3fff0430
3fff13e0: 3fffdad0 00000000 3fff0040 4020f8dd
3fff13f0: 4020e3dc 00000000 3fff0040 402123f0
3fff1400: feefeffe 3ffe9b70 3fff27ec 4020a83f
3fff1410: 3fffdad0 00000000 3fff00f8 4020f98b
3fff1420: 00000000 00000000 00000001 40207194
3fff1430: 3fffdad0 00000000 3fff0414 40212384
3fff1440: feefeffe feefeffe 3fff0430 4010070c
<<<stack<<<

Originally created by @thomsenle on GitHub (Feb 5, 2018). Original GitHub issue: https://github.com/tzapu/WiFiManager/issues/502 Hey, very cool to see the development of the wifimanger. I played around a little with the development version and always get a Exeption 28 when i run the Webportal permanent. My main loop only consists out of ` if (!webportalrunning) { wifiManager.startWebPortal(); webportalrunning = true; } else wifiManager.process();` In the debug i can see that its scans for the networks and then crashes and reboots. Unfortunatly i have no idea where to start searching for the error. I allready errased the flash totaly as suggested in a other issue. No change for me. Thanks for your help, Thomas Please let me know if you need more debug informations for testing. Debug output: *WM: Starting Web Portal *WM: HTTP server started *WM: <- HTTP Wifi *WM: Scan done *WM: DUP AP: FRITZ!Box Fon WLAN 7270 *WM: DUP AP: Vodafone Hotspot *WM: DUP AP: Vodafone Hotspot *WM: DUP AP: Vodafone Hotspot *WM: DUP AP: Vodafone Hotspot *WM: DUP AP: Vodafone Homespot *WM: DUP AP: Vodafone Homespot *WM: DUP AP: Vodafone Homespot *WM: DUP AP: Vodafone Homespot *WM: AP: -57 boingboing *WM: AP: -59 FRITZ!Box Fon WLAN 7270 *WM: AP: -67 Fritzbox-0815 *WM: AP: -67 Hallo Gast! WLAN *WM: AP: -69 WLAN-B8BAHX *WM: AP: -69 Telekom_FON *WM: AP: -80 KabelBox-3760 *WM: AP: -80 Vodafone Hotspot *WM: AP: -80 Vodafone Homespot *WM: AP: -82 FRITZ!Box 6490 Cable *WM: AP: -82 TP-LINK_AC1A06 *WM: AP: -87 NETGEAR88 *WM: AP: -88 KabelBox-364C *WM: AP: -89 TP-LINK_B732 *WM: AP: -89 HITRON-3420 *WM: AP: -90 gaensebluemchen *WM: AP: -91 Netzwerk_KW1509 *WM: AP: -92 vdr.fische.leipzig Stack-Trace: Exception (28): epc1=0x402151f0 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000001 depc=0x00000000 ctx: cont sp: 3fff1080 end: 3fff1450 offset: 01a0 >>>stack>>> 3fff1220: 3fff12f0 00000004 3fff125c 402118c2 3fff1230: 00000001 ff000000 3fff1274 4021179c 3fff1240: 3fff12f0 00000004 3fff0040 4020db1d 3fff1250: 00000000 00000000 00000000 3fff46cc 3fff1260: 0000000f 00000003 3fff6104 40100648 3fff1270: 00001404 3fff47f4 0000005f 00000050 3fff1280: 3fff45fc 0000006f 00000069 33373031 3fff1290: 00001500 3fff1314 3fff1314 402117f7 3fff12a0: ffffffff 0000000c 00000037 ffffffff 3fff12b0: 00000011 00000046 00000060 00000065 3fff12c0: 00000001 00000001 3fff12f0 4010068c 3fff12d0: 00000001 00000001 3fff0040 4020b9ec 3fff12e0: 00000001 00000001 3fff0040 4020ff47 3fff12f0: 3fff4674 0000004f 0000004a 00000000 3fff1300: 00000000 00000000 3fff600c 000000ef 3fff1310: 000000ec 3fff6104 0000155f 00001555 3fff1320: 00000001 00000001 3fff4284 40213664 3fff1330: 00000000 00000000 3fff4284 4020b9e2 3fff1340: 3fff4284 3fff38bc 3fff4284 4020ba1e 3fff1350: 00000000 00000000 00000000 402119a0 3fff1360: 3fff4284 3fff38bc 3fff387c 4020bab1 3fff1370: 3fff47ac 0000000f 00000005 40209f10 3fff1380: 3fff38bc 00000001 3fff0430 3fff38a0 3fff1390: 00000001 00000000 0000000f 3fff4284 3fff13a0: 00000000 00000000 3fff387c 3fff041c 3fff13b0: 00000001 3fff38a0 3fff387c 4020bd10 3fff13c0: 3fffdad0 00000000 3fff35ec 4020ad3d 3fff13d0: 00000000 3fff4774 40212338 3fff0430 3fff13e0: 3fffdad0 00000000 3fff0040 4020f8dd 3fff13f0: 4020e3dc 00000000 3fff0040 402123f0 3fff1400: feefeffe 3ffe9b70 3fff27ec 4020a83f 3fff1410: 3fffdad0 00000000 3fff00f8 4020f98b 3fff1420: 00000000 00000000 00000001 40207194 3fff1430: 3fffdad0 00000000 3fff0414 40212384 3fff1440: feefeffe feefeffe 3fff0430 4010070c <<<stack<<<

kerem commented

2026-02-28 01:25:12 +03:00

Author

Owner

@tablatronix commented on GitHub (Feb 5, 2018):

Do you have a full sketch or can reproduce with example ?
Ill test when I can

@tablatronix commented on GitHub (Feb 5, 2018): Do you have a full sketch or can reproduce with example ? Ill test when I can

kerem commented

2026-02-28 01:25:12 +03:00

Author

Owner

@thomsenle commented on GitHub (Feb 5, 2018):

Yes, im running the following code with the artnet-lib made by rstephan.
https://github.com/rstephan/ArtnetWifi

Used Version of the ESP8266 stuff for the IDE is 2.4.0-rc2.

`
/*
Example, transmit all received ArtNet messages (DMX) out of the serial port in plain text.

Stephan Ruloff 2016
https://github.com/rstephan

*/
#if defined(ARDUINO_ARCH_ESP32)
#include <WiFi.h>
#else
#include <ESP8266WiFi.h>
#endif

#include <WiFiUdp.h>
#include <ArtnetWifi.h>
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include <WiFiManager.h>
bool webportalrunning = false;

WiFiManager wifiManager;

WiFiUDP UdpSend;
ArtnetWifi artnet;

void onDmxFrame(uint16_t universe, uint16_t length, uint8_t sequence, uint8_t* data)
{
boolean tail = false;

Serial.print("DMX: Univ: ");
Serial.print(universe, DEC);
Serial.print(", Seq: ");
Serial.print(sequence, DEC);
Serial.print(", Data (");
Serial.print(length, DEC);
Serial.print("): ");

if (length > 16) {
length = 16;
tail = true;
}
// send out the buffer
for (int i = 0; i < length; i++)
{
Serial.print(data[i], HEX);
Serial.print(" ");
}
if (tail) {
Serial.print("...");
}
Serial.println();
}

void setup()
{

// put your setup code here, to run once:
Serial.begin(115200);

//WiFiManager
//Local intialization. Once its business is done, there is no need to keep it around
WiFiManager wifiManager;
//reset saved settings
//wifiManager.resetSettings();

//set custom ip for portal
//wifiManager.setAPStaticIPConfig(IPAddress(10,0,1,1), IPAddress(10,0,1,1), IPAddress(255,255,255,0));

//fetches ssid and pass from eeprom and tries to connect
//if it does not connect it starts an access point with the specified name
//here "AutoConnectAP"
//and goes into a blocking loop awaiting configuration
wifiManager.autoConnect("AutoConnectAP");
//or use this for auto generated name ESP + ChipID
//wifiManager.autoConnect();

//if you get here you have connected to the WiFi
Serial.println("connected...yeey :)");
artnet.setArtDmxCallback(onDmxFrame);
artnet.begin();
}

void loop()
{
if (!webportalrunning) {
wifiManager.startWebPortal();
webportalrunning = true;
} else wifiManager.process();
//artnet.read();
}
`

@thomsenle commented on GitHub (Feb 5, 2018): Yes, im running the following code with the artnet-lib made by rstephan. https://github.com/rstephan/ArtnetWifi Used Version of the ESP8266 stuff for the IDE is 2.4.0-rc2. ` /* Example, transmit all received ArtNet messages (DMX) out of the serial port in plain text. Stephan Ruloff 2016 https://github.com/rstephan */ #if defined(ARDUINO_ARCH_ESP32) #include <WiFi.h> #else #include <ESP8266WiFi.h> #endif #include <WiFiUdp.h> #include <ArtnetWifi.h> #include <DNSServer.h> #include <ESP8266WebServer.h> #include <WiFiManager.h> bool webportalrunning = false; WiFiManager wifiManager; WiFiUDP UdpSend; ArtnetWifi artnet; void onDmxFrame(uint16_t universe, uint16_t length, uint8_t sequence, uint8_t* data) { boolean tail = false; Serial.print("DMX: Univ: "); Serial.print(universe, DEC); Serial.print(", Seq: "); Serial.print(sequence, DEC); Serial.print(", Data ("); Serial.print(length, DEC); Serial.print("): "); if (length > 16) { length = 16; tail = true; } // send out the buffer for (int i = 0; i < length; i++) { Serial.print(data[i], HEX); Serial.print(" "); } if (tail) { Serial.print("..."); } Serial.println(); } void setup() { // put your setup code here, to run once: Serial.begin(115200); //WiFiManager //Local intialization. Once its business is done, there is no need to keep it around WiFiManager wifiManager; //reset saved settings //wifiManager.resetSettings(); //set custom ip for portal //wifiManager.setAPStaticIPConfig(IPAddress(10,0,1,1), IPAddress(10,0,1,1), IPAddress(255,255,255,0)); //fetches ssid and pass from eeprom and tries to connect //if it does not connect it starts an access point with the specified name //here "AutoConnectAP" //and goes into a blocking loop awaiting configuration wifiManager.autoConnect("AutoConnectAP"); //or use this for auto generated name ESP + ChipID //wifiManager.autoConnect(); //if you get here you have connected to the WiFi Serial.println("connected...yeey :)"); artnet.setArtDmxCallback(onDmxFrame); artnet.begin(); } void loop() { if (!webportalrunning) { wifiManager.startWebPortal(); webportalrunning = true; } else wifiManager.process(); //artnet.read(); } `

kerem commented

2026-02-28 01:25:12 +03:00

Author

Owner

@tablatronix commented on GitHub (Feb 6, 2018):

cannot reproduce, you dont say which branch or board.

Try moving WiFiManager wifiManager to global

Also you can decode the exception in ardunio with the exception decoder tool

@tablatronix commented on GitHub (Feb 6, 2018): cannot reproduce, you dont say which branch or board. Try moving WiFiManager wifiManager to global Also you can decode the exception in ardunio with the exception decoder tool

kerem commented

2026-02-28 01:25:12 +03:00

Author

Owner

@MatteoGheza commented on GitHub (Oct 30, 2021):

Having the same error (on a TTGO-T).
My code is similar to the code in the issue.
Here's a decoded stacktrace:

PC: 0x400014dc
EXCVADDR: 0x00000001

Decoding stack results
0x400ee42e: String::String(char const*) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\cores\esp32\WString.cpp line 35
0x400deae6: String::replace(__FlashStringHelper const*, char const*) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\cores\esp32/WString.h line 264
0x400e2545: WiFiManager::getParamOut() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 1629
0x400e3179: WiFiManager::handleParam() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 1305
0x4019c496: std::_Function_handler    (WiFiManager*)> >::_M_invoke(std::_Any_data const&) at c:\users\ardui\appdata\local\arduino15\packages\esp32\tools\xtensa-esp32-elf-gcc\1.22.0-97-gc752ad5-5.2.0\xtensa-esp32-elf\include\c++\5.2.0/functional line 600
0x400e0bca: std::function ::operator()() const at c:\users\ardui\appdata\local\arduino15\packages\esp32\tools\xtensa-esp32-elf-gcc\1.22.0-97-gc752ad5-5.2.0\xtensa-esp32-elf\include\c++\5.2.0/functional line 2271
0x400eb1a9: FunctionRequestHandler::handle(WebServer&, http_method, String) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WebServer\src\detail/RequestHandlersImpl.h line 45
0x400eb216: WebServer::_handleRequest() at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WebServer\src\WebServer.cpp line 636
0x400eb395: WebServer::handleClient() at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WebServer\src\WebServer.cpp line 315
0x400e6fea: WiFiManager::processConfigPortal() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 771
0x400e71c4: WiFiManager::process() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 757
0x400d2eee: loop() at C:\Users\ardui\progetti\TallyArbiter\listener_clients\TTGO_T-listener/TTGO_T-listener.ino line 701
0x400ef360: loopTask(void*) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\cores\esp32\main.cpp line 23
0x40090b1a: vPortTaskWrapper at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port.c line 143

Here that's the extended version of the code that triggered this error: https://github.com/josephdadams/TallyArbiter/blob/move_listener_clients/listener_clients/TTGO_T-listener/TTGO_T-listener.ino

I think that the bug could be in custom params reading.

PS: in this code WM is global

@MatteoGheza commented on GitHub (Oct 30, 2021): Having the same error (on a TTGO-T). My code is similar to the code in the issue. Here's a decoded stacktrace: ``` PC: 0x400014dc EXCVADDR: 0x00000001 Decoding stack results 0x400ee42e: String::String(char const*) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\cores\esp32\WString.cpp line 35 0x400deae6: String::replace(__FlashStringHelper const*, char const*) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\cores\esp32/WString.h line 264 0x400e2545: WiFiManager::getParamOut() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 1629 0x400e3179: WiFiManager::handleParam() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 1305 0x4019c496: std::_Function_handler (WiFiManager*)> >::_M_invoke(std::_Any_data const&) at c:\users\ardui\appdata\local\arduino15\packages\esp32\tools\xtensa-esp32-elf-gcc\1.22.0-97-gc752ad5-5.2.0\xtensa-esp32-elf\include\c++\5.2.0/functional line 600 0x400e0bca: std::function ::operator()() const at c:\users\ardui\appdata\local\arduino15\packages\esp32\tools\xtensa-esp32-elf-gcc\1.22.0-97-gc752ad5-5.2.0\xtensa-esp32-elf\include\c++\5.2.0/functional line 2271 0x400eb1a9: FunctionRequestHandler::handle(WebServer&, http_method, String) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WebServer\src\detail/RequestHandlersImpl.h line 45 0x400eb216: WebServer::_handleRequest() at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WebServer\src\WebServer.cpp line 636 0x400eb395: WebServer::handleClient() at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WebServer\src\WebServer.cpp line 315 0x400e6fea: WiFiManager::processConfigPortal() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 771 0x400e71c4: WiFiManager::process() at C:\Users\ardui\Documents\Arduino\libraries\WiFiManager\WiFiManager.cpp line 757 0x400d2eee: loop() at C:\Users\ardui\progetti\TallyArbiter\listener_clients\TTGO_T-listener/TTGO_T-listener.ino line 701 0x400ef360: loopTask(void*) at C:\Users\ardui\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\cores\esp32\main.cpp line 23 0x40090b1a: vPortTaskWrapper at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port.c line 143 ``` Here that's the extended version of the code that triggered this error: https://github.com/josephdadams/TallyArbiter/blob/move_listener_clients/listener_clients/TTGO_T-listener/TTGO_T-listener.ino I think that the bug could be in custom params reading. PS: in this code WM is global