from https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_en#new_gpio_map I use
IO index ESP8266 pin
1 GPIO5
2 GPIO4
I make some test with G3MB-202P Solid State Relay. It works on my ESP-12 with NodeMCU 0.9.5 build 20150212. The output high Voltage is 3.2V and my relay switch on at 2.6V. But I have to use the index:
IO index ESP8266 pin
2 GPIO5
1 GPIO4
What is wrong?
Peter