Error on sending AT+CWJAP_DEF commands to ESP8266 - arduino

Question

I am trying to send AT commands to ESP8266 to get connected with internet with the Wifi.
When I am sending AT and AT+RST command on serial monitor then I am getting OK and ready response which seems perfect.
Then I am sending AT+CWLAP to get list of available wifi networks which is also executing correctly.
AT+CWLAP
+CWLAP:(3,"Moto",-42,"a4:70:d6:7a:fa:6c",1,25,0)
+CWLAP:(4,"PRANJAL",-95,"1c:a5:32:3d:f5:c4",1,-16,0)
+CWLAP:(2,"VIHAN",-94,"c8:3a:35:2f:1d:81",1,-21,0)
+CWLAP:(3,"Tenda",-93,"c8:3a:35:20:a9:b1",9,-4,0)
OK
Then I sent AT+CWMODE? which is also perfect.
AT+CWMODE?
+CWMODE:1
OK
Now I am trying to connect ESP8266 with above listed Wifi with this command, it is sending an ERROR on serial monitor.
AT+CWJAP_DEF="Moto","reset1234"
Error
⸮=IRe"Moto","reset1234"
ERROR
Can anyone suggest me what could be the reason of this issue ?
#include "SoftwareSerial.h"
SoftwareSerial esp8266(2, 3); // RX, TX
void setup()
{
Serial.begin(9600); // serial port used for debugging
esp8266.begin(9600); // your ESP's baud rate might be different
}
void loop()
{
if(esp8266.available()) // check if the ESP is sending a message
{
while(esp8266.available())
{
char c = esp8266.read(); // read the next character.
Serial.write(c); // writes data to the serial monitor
}
}
if(Serial.available())
{
delay(10); // wait to let all the input command in the serial buffer
// read the input command in a string
String cmd = "";
while(Serial.available())
{
cmd += (char)Serial.read();
}
// send to the esp8266
esp8266.println(cmd);
}
}

Answer 1

The current official AT command set seems to be documented on https://github.com/espressif/ESP8266_AT/wiki/AT_Description
http://espressif.com/sites/default/files/documentation/4a-esp8266_at_instruction_set_en.pdf
https://www.itead.cc/wiki/ESP8266_Serial_WIFI_Module#AT_Commands
If the module is to be configured as a client, i.e. to connect to an access point, the following AT commands have to be sent (11500 baud 8N1, CR-LF line termination):
AT+RST
AT+CWMODE=3 (1 is "Station" only (wifi client), 3 is mixed mode "Station and Access-Point", both should work)
AT+CWJAP="Moto","reset1234"
AT+CWJAP_CUR="Moto","reset1234" (temporary) or
AT+CWJAP_DEF="Moto","reset1234" (stored)
For reference, a "success story" (ESP8266 module with USB-UART, Software: HTerm, Access Point with WPA2 (both TKIP / CCMP tested)):
AT<\r><\r><\n><\r><\n>
OK<\r><\n>
AT+RST<\r><\r><\n><\r><\n>
OK<\r><\n>
<\r><\n>
ets Jan 8 2013,rst cause:2, boot mode:(3,6)<\r><\n>
<\r><\n>
load 0x40100000, len 1856, room 16 <\r><\n>
tail 0<\r><\n>
chksum 0x63<\r><\n>
load 0x3ffe8000, len 776, room 8 <\r><\n>
tail 0<\r><\n>
chksum 0x02<\r><\n>
load 0x3ffe8310, len 552, room 8 <\r><\n>
tail 0<\r><\n>
chksum 0x79<\r><\n>
csum 0x79<\r><\n>
<\r><\n>
2nd boot version : 1.5<\r><\n>
SPI Speed : 40MHz<\r><\n>
SPI Mode : DIO<\r><\n>
SPI Flash Size & Map: 32Mbit(512KB+512KB)<\r><\n>
jump to run user1 # 1000<\r><\n>
<\r><\n>
??r?d?l<18>?<31><\0><\f>?l`<3>??s?l?<28>?<19>?<4><4><4>$ <2>??r?$<4>??<27>?<4><4>ll`<3>r$?<18>?"<\0>????"<4>l?cs|<\f>?`?22???<27>BB<18>c??o??<18>NN?<16><2><\0><2>d$??<2>d??<\0>?<4>d??<\0>ll????d??l`<2>?<2>N?<\0>????"<4>d??<28>p<4><4><2><2>???"b<4>$<4>?"prlrl<\r><\n>
Ai-Thinker Technology Co. Ltd.<\r><\n>
<\r><\n>
ready<\r><\n>
WIFI DISCONNECT<\r><\n>
AT+CWMODE?<\r><\r><\n>+CWMODE:3<\r><\n>
<\r><\n>
OK<\r><\n>
AT+CWJAP_CUR="Moto","reset1234"<\r><\r><\n>
WIFI CONNECTED<\r><\n>
WIFI GOT IP<\r><\n>
<\r><\n>
OK<\r><\n>
AT+CIFSR<\r><\r><\n>+CIFSR:APIP,"0.0.0.0"<\r><\n>
+CIFSR:APMAC,"00:00:00:00:00:00"<\r><\n>
+CIFSR:STAIP,"0.0.0.0"<\r><\n>
+CIFSR:STAMAC,"00:00:00:00:00:00"<\r><\n>
<\r><\n>
OK<\r><\n>
AT+GMR<\r><\r><\n>AT version:1.1.0.0(May 11 2016 18:09:56)<\r><\n>
SDK version:1.5.4(baaeaebb)<\r><\n>
Ai-Thinker Technology Co. Ltd.<\r><\n>
Jun 13 2016 11:29:20<\r><\n>
OK<\r><\n>
This also works with mode=1.
Major rewrite.
Questions and ideas to test:
what is your module firmware version?
access point issues (e.g. MAC address restrictions)?
power supply good?
might there be any old configuration or other code running on the module?
what is the byte code of ⸮ in the error message - Is it two bytes 0x2E2E?
are you using the Arduino serial monitor for communication?
in contrast to my comment, maybe the arduino does have an influence (timing?). Try to rule this out by
doing the pass-through character-based instead of line-based, e.g.:
(end of list, no code possible otherwise:)
loop(){
if( esp8266.available() )
Serial.write(esp8266.read());
if( Serial.available() )
esp8266.write(Serial.read());
}
keeping the AVR in reset and connecting the ESP8266 serial lines directly to the USB-UART converter

Answer 2

Alright! I just tried to connect with different wifi and it got connected with it. It was some kinda issue with mobile hotspot.