WEMOS MEGA 2560 + ESP8266 built-in

[paolinor70]

HI, I bought the INTEGRATED BOARD as above.
I have problems in communicating between the MEGA and the ESP01 module which is inside.
AT command does not receive OK.

1. The MEGA 2560 works fine alone.
2. I already FLASHED the ESP01 with this software ESP8266 Firmware - ElectroDragon Wiki
3. message from ESP DOWNLOADTOOL v.3.6.6 was OK
4. using 1 simple sketch for communicating between the two parts, every 5 seconds via serial3 MEGA receive this:

ets Jan 8 2013,rst cause:4, boot mode:(3,6)

wdt reset
load 0x40100000, len 1856, room 16
tail 0
chksum 0x63
load 0x3ffe8000, len 776, room 8
tail 0
chksum 0x02
load 0x3ffe8310, len 552, room 8
tail 0
chksum 0x79
csum 0x79

2nd boot version : 1.5
SPI Speed : 40MHz
SPI Mode : DIO
SPI Flash Size & Map: 32Mbit(512KB+512KB)
jump to run user1 @ 1000

Any IDEA or suggestion to fix the problem?

The sketch I used is under reported

Thanks
p.

void setup() {
Serial.begin(115200);
Serial3.begin(115200);
pinMode(13,OUTPUT);
delay(500);
Serial.println("AT+CIPMUX=1");
Serial3.println("AT+CIPMUX=1");
delay(2000);
Serial.println("AT+CIPSERVER=1,5000");
Serial3.println("AT+CIPSERVER=1,5000");
delay(2000);
Serial.println("AT+CIPSERVER=1,5000");
Serial3.println("AT+CIPSTO=3600");
delay(2000);
}

void loop() {
// listen for communication from the ESP8266 and then write it to the serial monitor
if ( Serial3.available() ) { Serial.write( Serial3.read() ); }

// listen for user input and send it to the ESP8266
if ( Serial.available() ) { Serial3.write( Serial.read() ); }
}

[Juraj]

why do you flash so old AT firmware? flash 1.7.1

AT | Espressif Systems

with
esptool.py write_flash --flash_size 2MB-c1 0x0 boot_v1.7.bin 0x01000 at/1024+1024/user1.2048.new.5.bin 0x1fb000 blank.bin 0x1fc000 esp_init_data_default_v08.bin 0xfe000 blank.bin 0x1fe000 blank.bin

yes, use the 2MB-c1 setting

[paolinor70]

Hi SOLVED!

I do not know how, but the problem was the FLASH procedure.
In order to solve I followed these steps:

1. ESP8266 module comes without the necessary AT command firmare inside.
2. Therefore to comunicate between MEGA and ESP it is necessary to install in the FLASH of ESP the AT firmware. you must:
   2a look for the flash program (flash_download_tools_v3.6.7) ESP8266EX Resources | Espressif Systems (choose ESP FLASH DOWLOAD TOOL)
   2b look for the AT command file (At_firmware_bin1.54) http://www.electrodragon.com/w/File:At_firmware_bin1.54.zip,
   2c FLASH.
   2c1 set the 8 switch at: sw1,2,3,4 to OFF ; sw 5,6,7 to ON (8 not used)
   2c2 push once the MODE button
   2c3 launch the FLASH program: (choose ESP8266 in the MENU)
   SETTINGS
   SPI Speed = 80MHz
   SPI Mode = DIO
   Flash Size = 32Mbit 4mb bytes x 8 bits = 32m bits
   Crystal Freq = 26M
   Speed = 921600
   file to upload: 1 file only. AiThinker_ESP8266_32Mbit set address 0x00000
   2c4 press the mode button on the board
   2c5 start procedure setting
   3 change switch to 1,2,3,4 ON, 5,6,7 OFF

done!

p.