ESP-01 Quick Reference
This short page offers some handy graphics for those using the ESP8266 ESP-01 WiFi Board.
Keep in mind, the boards have more than one revision and this solely represents the boards in my possession.
There are other schematics on the internet. I found them a little cumbersome and ambiguous. Therefore I created my own. I cleared up the ambiguities by actually metering the circuit out.
ESP8266 ESP-01 Pin Outs
The illustration below shows the Pin Outs of the ESP-01 pin outs. These pins can serve different functions that are discussed in other articles.
At the heart of the Chip is the ESP8266 System On a Chip. The illustration below shows the pin numbering. A more complete explanation of the pin functions can be found here.