I have this module:
It works perfectly fine with arduino but when I attach the esp8266 gpio pin 0 to one of its input pins it doesn't change the state (the relay module built-in led flicker a little but failed to change the relay state.) the relay is attached to 5v vcc and the esp to 3.3v with at least 400ma.
do I need something more to drive the 5v input with 3.3 esp output? isn't 3.3 counts as 5v ~?
I herd once the the esp gpio out is only few ma and maybe insufficient when driving 5v signal, is this true? what do I need to add(and if I can get schema it will be much better) between esp gpio to relay module io pin to drive it?