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Showing posts from November, 2017

ESP GPIO pins...

The ESP8266 can easily be programmed with the Arduino IDE and the main benefit using it, is the WiFi interface that reduces your communication wiring to zero. A $5 Raspberry Pi Zero W with a $5 micro SD Card becomes your Access Point, DHCP Server, Gateway to the Internet, and will also run applications like JMRI and MQTT. But, now that you have a well connected $3 ESP-xx device, what pins are available to do what? We are not counting the Rx and Tx pins, you could reassign those for your own purpose, but the boot loader is going to talk at startup and updating your firmware might need these pins, so think ahead. There is some information here , but when you are writing the "Arduino" code for the ESP8266, you need a little more guidance... The ESP-01 has 2 GPIO pins, so you can do a 3 color signal, 2 relays, 2 digital sensors, or use them for i2c to a port expander and the rest is easy. The ESP-05 has none, only the RST, RXD and TXD pins...good WiFi shield, if you hav