Arduino code for a multi use sensor, which repots in MQTT based on the ESP8266 chip. Intended to cost less than a �10.
Details: Tested on Arduino IDE 1.6.5 and ESP01+ESP12 ESP8266 modules See https://thefrinkiac7.wordpress.com/esp8266-modules/ for details of hardware construction
The MQTT client name will be ESP8266-{mac address} for uniqueness
NB: We're using the MQTTClient library, rather than pubsubclient as it seemed to be more stable with the ESP8266 module.
Current features: 1-wire temperature sensors (DSB1820) Ability to switch off sensor when not in use (not really needed for a DSB1820, but may be for other sensors) Super-power save for modules where the reset line is broken out Ability to switch a number of Neopixel RGB LEDs under control of MQTT message (format message as: "RRR GGG BBB ttt" (no "s) where R G and B are 000-255 with leading zeros and ttt is ms between each LED's update) Ability to read pulses from a gas meter and report as MQTT Reboots microcontroller once a day in case of memory leaks Reboot of microcontroller if MQTT connection is lost or if WiFi doesn't connection Reboot routine tests to see if the GPIO0 is low, won't reboot until it's high, as this is the program flash line and will result in booting to program mode and non-operational controller
To Do: "mqtt log" flag and code up logging to mqtt for off-serial hook up See if a DSB1820 can be run from parasite power using the internal pullup IO lines. Basic API to allow different neo-pixel effects (strobe, rainbow, whoosh, etc)
Gotchas: If using GPIO0 for Gas Sensor, if the sensor is activated when you start the ESP8266 it will go into program mode and not start the sketch - Use another GPIO line!! or disconnect sensors before boot!