ESP8266 Community Forum

- Thu May 14, 2020 10:40 pm #87106 I thought I sent this earlier, but I can't find it in my history on on the board anywhere... hopefully not spamming here.

I'll do my best to provide the information that'll be helpful.

I'm using Platform IO, configured with a heltec_wifi_kit_32 board and the arduino framework. No pio libs installed.

When I build and upload the code, it starts the access point, and I can connect to it.
When I rebuild it (unchanged) and upload, and reconnect, it drops the esp into a reboot loop with a stack dump on the serial monitor.
If I change the ssid, and build and upload, it works once.

It seems like there is something I'm missing in my WiFi code, or there's a bug in the dhcp library when a client has an existing lease.

Any advice appreciated.

The code:

Code: Select all#include <WiFi.h>
#include <WebServer.h>
#include <DNSServer.h>

IPAddress ip(192, 168, 1, 1);

void setup() {
  delay(3000);

  WiFi.disconnect();
  WiFi.mode(WIFI_OFF);

  WiFi.mode(WIFI_AP);
  WiFi.softAPConfig(ip, ip, IPAddress(255, 255, 255, 0));
  WiFi.softAP("test");
}

void loop() { }


Code: Select allRebooting...
ets Jun  8 2016 00:22:57

rst:0xc (SW_CPU_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:2
load:0x3fff0018,len:4
load:0x3fff001c,len:1044
load:0x40078000,len:8896
load:0x40080400,len:5828
entry 0x400806ac
dhcps: send_offer>>udp_sendto result 0
Guru Meditation Error: Core  0 panic'ed (InstrFetchProhibited). Exception was unhandled.
Core 0 register dump:
PC      : 0x00000000  PS      : 0x00060e30  A0      : 0x8010dfd9  A1      : 0x3ffb3b40 
A2      : 0x3ffcb660  A3      : 0x3ffcbc0c  A4      : 0x3ffbda68  A5      : 0x3ffbda48 
A6      : 0x0201a8c0  A7      : 0x0c01a8c0  A8      : 0x8010de7c  A9      : 0x3ffb3b00 
A10     : 0x3ffcb670  A11     : 0x3ffcbc0c  A12     : 0x3ffb3b4c  A13     : 0x00000044 
A14     : 0x00000001  A15     : 0x00000006  SAR     : 0x00000010  EXCCAUSE: 0x00000014 
EXCVADDR: 0x00000000  LBEG    : 0x4000c349  LEND    : 0x4000c36b  LCOUNT  : 0x00000000 

Backtrace: 0x00000000:0x3ffb3b40 0x4010dfd6:0x3ffb3b80 0x40116515:0x3ffb3ba0 0x4011b51d:0x3ffb3be0 0x40120642:0x3ffb3c00 0x4010e1a3:0x3ffb3c20 0x400886e1:0x3ffb3c50
  #0  0x00000000:0x3ffb3b40 in ?? ??:0
  #1  0x4010dfd6:0x3ffb3b80 in handle_dhcp at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/lwip/apps/dhcpserver/dhcpserver.c:1031
  #2  0x40116515:0x3ffb3ba0 in udp_input at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/lwip/lwip/src/core/udp.c:401
  #3  0x4011b51d:0x3ffb3be0 in ip4_input at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/lwip/lwip/src/core/ipv4/ip4.c:740
  #4  0x40120642:0x3ffb3c00 in ethernet_input at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/lwip/lwip/src/netif/ethernet.c:184
  #5  0x4010e1a3:0x3ffb3c20 in tcpip_thread at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/lwip/lwip/src/api/tcpip.c:483
  #6  0x400886e1:0x3ffb3c50 in vPortTaskWrapper at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port.c:355 (discriminator 1)