Uso ESP8266 WiFi Shields | tecno4 | Scoop.it
From aprendiendoarduino.wordpress.com - March 16, 2019 8:01 AM
Web: https://wiki.wemos.cc/products:d1_mini_shields:relay_shield

Esquematico: https://wiki.wemos.cc/_media/products:d1_mini_shields:sch_relay_v2.0.0.pdf

Se maneja con el Pin D1

Ejemplo: https://github.com/wemos/D1_mini_Examples/blob/master/examples/04.Shields/Relay_Shield/BlinkWithoutDelay/BlinkWithoutDelay.ino