Arduino: Exception(2) after connect to Accespoint

Created on 13 Mar 2016 · 3Comments · Source: esp8266/Arduino

Basic Infos

Hardware

Hardware: ESP-01
Core Version: 2.1.0 (via "stable" in Board-Manager; Arduino 1.6.8)

Description

Exception(2) after connect to Accesspoint.

I am using a ESP-01 with Arduino 1.6.8. I started with the Serial Telnet Example and are getting the above Exception after I got a connection to my acces point.

I tested using two different ESP-Modules.

The epc1=0x3ffe86d0 is constant, so no sparadic problem.

I used two different Access Points an different WPA settings.

Power is from a 3.3V 800 mA Buck power Supply from 12V 2 Amp Supply, not extra capacitors.

Serial is a FTDI 3,3V Board.

I included the elf file and the sketch here:
elf_and_bin.zip
sketch.zip

I have kept the reset of the sketch-temp-folder, if you need more

The error is 100% reproducible with other sekteches in my envoronment. Strangely using the Wifimanager (another sektch) works - you can connect to the accespoint, access the captive gui and choose a wifi. As soon as you have done that the same error occurs until you reset the wfifimanger-data.

Any ideas?

Thanks in advance.

Settings in IDE

Module: Generic ESP8266 Module
Flash Size: 512K (64K SPIFFS)
CPU Frequency: 80Mhz
Flash Mode: DIO
Flash Frequency: 40Mhz
Upload Using: SERIAL
Reset Method: ck

Sketch

include

//how many clients should be able to telnet to this ESP8266

define MAX_SRV_CLIENTS 1

const char* ssid = "markusTest";
const char* password = "passwdTestasdf";

WiFiServer server(23);
WiFiClient serverClients[MAX_SRV_CLIENTS];

void setup() {
Serial.begin(115200);
WiFi.begin(ssid, password);
Serial.print("\nConnecting to "); Serial.println(ssid);
uint8_t i = 0;
while (WiFi.status() != WL_CONNECTED && i++ < 20) delay(500);
if(i == 21){
Serial.print("Could not connect to"); Serial.println(ssid);
while(1) delay(500);
}
//start UART and the server
Serial.begin(115200);
server.begin();
server.setNoDelay(true);

Serial.print("Ready! Use 'telnet ");
Serial.print(WiFi.localIP());
Serial.println(" 23' to connect");
}

void loop() {
uint8_t i;
//check if there are any new clients
if (server.hasClient()){
for(i = 0; i < MAX_SRV_CLIENTS; i++){
//find free/disconnected spot
if (!serverClients[i] || !serverClients[i].connected()){
if(serverClients[i]) serverClients[i].stop();
serverClients[i] = server.available();
Serial.print("New client: "); Serial.print(i);
continue;
}
}
//no free/disconnected spot so reject
WiFiClient serverClient = server.available();
serverClient.stop();
}
//check clients for data
for(i = 0; i < MAX_SRV_CLIENTS; i++){
if (serverClients[i] && serverClients[i].connected()){
if(serverClients[i].available()){
//get data from the telnet client and push it to the UART
while(serverClients[i].available()) Serial.write(serverClients[i].read());
}
}
}
//check UART for data
if(Serial.available()){
size_t len = Serial.available();
uint8_t sbuf[len];
Serial.readBytes(sbuf, len);
//push UART data to all connected telnet clients
for(i = 0; i < MAX_SRV_CLIENTS; i++){
if (serverClients[i] && serverClients[i].connected()){
serverClients[i].write(sbuf, len);
delay(1);
}
}
}
}
`

Debug Messages

Connecting to markusTest
Ready! Use 'telnet 192.168.178.30 23' to connect

Exception (2):
epc1=0x3ffe86d0 epc2=0x00000000 epc3=0x00000000 excvaddr=0x3ffe86d0 depc=0x00000000

ctx: sys
sp: 3ffffc90 end: 3fffffb0 offset: 01a0

stack>>>
3ffffe30: 40211835 3ffffed0 3ffed830 3ffed258
3ffffe40: 40211895 3ffffed0 4021177d 3ffffed0
3ffffe50: 6b72616d 65547375 40007473 00000100
3ffffe60: 7fffffff 3ffe9650 3ffe9650 00000001
3ffffe70: 4020df59 00080000 3fffc200 00000022
3ffffe80: ffffffda 00000004 3ffffee0 3ffffef1
3ffffe90: 40107020 00000000 3fff0f18 000adeab
3ffffea0: 4010549c 00000001 000000a5 3fff0114
3ffffeb0: 3fff00fc 00000000 00000000 3ffffe40
3ffffec0: 402038c0 3ffeef3c 00000000 3fffd9d0
3ffffed0: 3ffffef0 3ffffee0 00000004 00000045
3ffffee0: 3ffeafb0 3ffe87dc 3fff0f18 000000e5
3ffffef0: 000000a5 00003a98 3ffeafbc 00000000
3fffff00: 00000000 00000000 3ffeafcb 4010031d
3fffff10: 00000000 00000f28 3ffeeef0 40100426
3fffff20: 40209402 00000000 0000003a 40100537
3fffff30: 4020707c 3ffee354 3fff0064 401008c1
3fffff40: 40211e8e 3ffec830 00000000 40107218
3fffff50: 3ffeaf8c 000000aa 00000000 4021c969
3fffff60: 00000000 40223ab1 3ffee608 3ffee630
3fffff70: 018e2c54 60000600 3ffe8ec0 3ffe8ec0
3fffff80: 40223af6 3fffdab0 00000000 3fffdcb0
3fffff90: 3ffee658 3fffdad0 3ffeef3c 402038e3
3fffffa0: 40000f49 40000f49 3fffdab0 40000f49
<<

ets Jan 8 2013,rst cause:2, boot mode:(1,6)

ets Jan 8 2013,rst cause:4, boot mode:(1,6)

wdt reset

Stack Decoded:

Decoding 23 results
0x40211835: scan_parse_beacon at ?? line ?
0x40211895: scan_parse_beacon at ?? line ?
0x4021177d: scan_parse_beacon at ?? line ?
0x4020df59: ieee80211_parse_beacon at ?? line ?
0x40107020: printf at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266/libc_replacements.c line 206
0x4010549c: chm_get_current_channel at ?? line ?
0x402038c0: loop_task at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266/core_esp8266_main.cpp line 43
0x4010031d: check_poison at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266\umm_malloc/umm_malloc.c line 817
0x40100426: check_poison_block at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266\umm_malloc/umm_malloc.c line 851
0x40209402: esf_buf_recycle at ?? line ?
0x40100537: check_poison_all_blocks at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266\umm_malloc/umm_malloc.c line 880
0x4020707c: ppRecycleRxPkt at ?? line ?
0x401008c1: free at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266\umm_malloc/umm_malloc.c line 1717
0x40211e8e: sta_input at ?? line ?
0x40107218: vPortFree at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266/heap.c line 18
0x4021c969: sys_check_timeouts at ?? line ?
0x40223ab1: ets_timer_handler_isr at ?? line ?
0x40223af6: ets_timer_handler_isr at ?? line ?
0x402038e3: loop_task at C:\Users\markus\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.1.0\cores\esp8266/core_esp8266_main.cpp line 43

troubleshooting

Source

mreschka

Most helpful comment

Hi... change your sketch setup: remove the line with
server.setNoDelay(true)

or change the parameter to false.... it worked for me.

for more information have a look at issue #1695

greetz fussel

fussel1976 on 16 Mar 2016

👍3 😄1

All 3 comments

I'm also getting this with the included telnet serial example on a ESP-12 (adafruit huzzah if that matters) on board package version 2.1.0 but it works fine on 2.0.0. many other examples work fine.

my serial output is:
`
ets Jan 8 2013,rst cause:2, boot mode:(3,6)

load 0x4010f000, len 1264, room 16
tail 0
chksum 0x42
csum 0x42
~ld

Exception (2):
epc1=0x3ffe849f epc2=0x00000000 epc3=0x00000000 excvaddr=0x3ffe849c depc=0x00000000

ctx: sys
sp: 3ffffc90 end: 3fffffb0 offset: 01a0

stack>>>
3ffffe30: 40211601 3ffffed0 3ffed5c0 3ffecfac
3ffffe40: 40211661 3ffffed0 40211549 3ffffed0
3ffffe50: 736c6977 00006e6f 40103052 00000100
3ffffe60: 7fffffff 3ffe93d4 3ffe93d4 00000001
3ffffe70: 4020dd25 00080000 00000004 40107208
3ffffe80: 00000000 00000004 3ffffee0 3ffffef1
3ffffe90: 40107020 00000000 3fff0518 000611c1
3ffffea0: 4010549c 00000030 000000a5 ffffffff
3ffffeb0: 402036b3 00000000 00000000 3ffffe40
3ffffec0: feefeffe 00000000 3fffd9d0 3ffeeccc
3ffffed0: 3ffffef0 3ffffee0 00000004 3ffeece0
3ffffee0: 00000000 3ffe8595 3fff0518 000000e5
3ffffef0: 000000a5 00003a98 3ffee3d0 00000030
3fffff00: 00000000 00000000 00000000 4010031d
3fffff10: 00000000 00000798 3ffeec80 40100426
3fffff20: 402091ce 00000000 00000020 40100537
3fffff30: 40206e48 3ffee0e4 3ffefdf4 401008c1
3fffff40: 40211c5a 3ffec5c0 00000000 40107218
3fffff50: 00000000 00000000 00000001 4021c735
3fffff60: 00000000 4022387d 3ffee398 3ffee3c0
3fffff70: 0013c9ad 60000600 3ffe8c28 4022387d
3fffff80: 402238c2 3fffdab0 00000000 3fffdcb0
3fffff90: 3ffee3e8 3fffdad0 3ffeeccc 402036ab
3fffffa0: 40000f49 40000f49 3fffdab0 40000f49
<< `