Simple Internet of Things Widget
Much more info below:
The ESP8266 is a little $3 module that allows devices to be controlled directly from the internet.
With an 80MHz processor and running Open Source firmware, they are becoming handy fun devices to forward the connectivity of anything cheaply and reliably.
Replace the LED with a resistor and transistor and anything can then be internet controlled.
This video shows a Simple IoT Widget, a germanium RF diode, in series with a red LED.
Depending on what the module is doing, the LED will show the WiFi output, using a very simple wireless electricity type of power transfer.
Just a handy toolbox sort of device, to save much head scratching when debugging code !
Many thanks to Julian illett, for his fantastic set of videos, which really helped my own projects to get started. You may notice the similarity of my battery powered assembly to his 😉
Here are some tips, from experience, if you wish to experiment with the ESP8266.
My FTDI232R Serial board got crippled in Windows 7, but still works fine in Linux afterward.
The cripple seems to be a registry event when installing the official drivers, rather than affecting the onboard chip.
Set it to 3.3V not 5V
If running Linux, the esp8266_flasher.exe from Espressif themselves works great for flashing of the nodemcu firmware. Runs fine under Wine if the USB port is mapped to COM1. Code tip from http://ubuntuforums.org/showthread.php?t=1335098, which is
ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com1
Update the ESP8266 nodemcu firmware to ‘latest’, as contained in the ‘pre-build’ folder of the nodemcu-firmware download. If it’s an older version, you can end up with compile errors and/or a constantly rebooting module.
For a constantly rebooting module, flash with original Espressif firmware, reboot, then flash again with Nodemcu firmware (latest). Otherwise you end up replacing the Nodemcu firmware with the same one and nothing gets fixed !
ESPlorer works great for Lua uploads. Just remember to always name a program init.lua for it to autoboot. Unplug and replug the module after uploading, to initialise the uploaded program. Do a ‘Reload’ to check there are not 2x init.lua with 1 of them showing as 0 bytes. If so, firmware on the module needs to be updated.
Use rechargeable AA batteries for portable power.
My 2x Energizer AA’s are 2500mAh, 2.8V
No idea yet of run time.
Typically, it seems the ESP8266-01 uses between 70mAh and 250mAh when active and not in a Sleep mode.
For USB or other, use a smoothed output LM317T or similar voltage regulator for a clean 3.3V
https://www.fairchildsemi.com/datasheets/LM/LM317.pdf
