This example implement:

• MQTT Publish the Message
• MQTT Subscribe the Topic
• MQTT works with SSL/TLS
• MQTT works with one-way anthentication
• MQTT works with two-way anthentication

you could choose mosquitto or EMQTT as your MQTT broker

All you need to configurate are in mqtt_config.h, please according to the comment to modify:

• CFG_HOLDER
• MQTT_HOST
• MQTT_PORT
• MQTT_CLIENT_ID
• MQTT_USER
• MQTT_PASS
• STA_SSID
• STA_PASS
• DEFAULT_SECURITY
• CA_CERT_FLASH_ADDRESS
• CLIENT_CERT_FLASH_ADDRESS

if you configurate DEFAULT_SECURITY to ONE_WAY_ANTHENTICATION or TWO_WAY_ANTHENTICATION, please according to tools/README.txt to generate your certificate

$./gen_misc.sh

compile options: 1 1 2 0 5, or others if you are familar to it.

Any way is OK,such as:

$~/esp/esp-idf/components/esptool_py/esptool/esptool.py --port /dev/ttyUSB0 --baud 921600 write_flash 0x00000 ~/ESP8266_NONOS_SDK/bin/boot_v1.6.bin 0x1000 ../bin/upgrade/user1.2048.new.5.bin 0x1fe000 ~/ESP8266_NONOS_SDK/bin/blank.bin 0x1fc000 ~/ESP8266_NONOS_SDK/bin/esp_init_data_default.bin

Any way is OK, but your flashing address is same as the Step 2,such as:

$~/esp/esp-idf/components/esptool_py/esptool/esptool.py --port /dev/ttyUSB0 --baud 921600 write_flash  0x77000 ~/ESP8266_NONOS_SDK/tools/bin/esp_ca_cert.bin
$~/esp/esp-idf/components/esptool_py/esptool/esptool.py --port /dev/ttyUSB0 --baud 921600 write_flash  0x78000 ~/MQTTESP8266/tools/bin/esp_cert_private_key.bin

when the demo starts up:

• it would subscribe the topic /mqtt/topic/0 , /mqtt/topic/1 , /mqtt/topic/2
• it would publish the topic /mqtt/topic/0 , /mqtt/topic/1 , /mqtt/topic/2
• MQTT broker would receive subscribe and publish

why the demo connect the WiFi failed?

• try to modify CFG_HOLDER

why the handshake failed?

• try to uncomment espconn_secure_set_size and modify memory allocate
• make sure your MQTT broker SSL/TLS certificate configurate valid