A simple IoT temperature, humidity and pressure sensor for NodeMCU / Lua and submitting measurements by MQTT API.
Above is a block diagram of the system.
To use the code, copy init.default.lua to init.lua, and nodevars.default.lua to nodevars.lua and customise the latter to suit your needs.
Enter your own APIKEY as appropriate.
The deep sleep function used depends on an external connection which you must make for it to work properly: connect a SB or germainium diode anode to RST, cathode to GPIO16 (D0).
See project described at https://owenduffy.net/blog/?p=13517.
Tested on: NodeMCU 3.0.0.0 built on nodemcu-build.com provided by frightanic.com branch: release commit: d4ae3c364bd8ae3ded8b77d35745b7f07879f5f9 release: release DTS: 202105102018 SSL: true build type: float LFS: 0x0 bytes total capacity modules: adc,bit,bme280_math,dht,encoder,file,gpio,http,i2c,mdns,mqtt,net,node,ow,sntp,spi,tmr,uart,wifi,tls build 2021-06-10 08:45 powered by Lua 5.1.4 on SDK 3.0.1-dev(fce080e)