MQTT subscriber example
[lpc1224] / apps / base /
drwxr-xr-x   ..
drwxr-xr-x - adc
drwxr-xr-x - cc1101
drwxr-xr-x - dht11
drwxr-xr-x - eeprom
drwxr-xr-x - epaper
drwxr-xr-x - gpio_intr
drwxr-xr-x - i2c_temp
drwxr-xr-x - i2c_uv
drwxr-xr-x - lcd_char
drwxr-xr-x - ledstrip
drwxr-xr-x - microphone
drwxr-xr-x - mqtt_pub
drwxr-xr-x - mqtt_sub
drwxr-xr-x - oled
drwxr-xr-x - power_down
drwxr-xr-x - rtc_pcf85363
drwxr-xr-x - servomotor
drwxr-xr-x - test_sensor_env
drwxr-xr-x - ultrasonic_sensor
drwxr-xr-x - usd_card
drwxr-xr-x - watchdog