Make sure you read and understand http://nodemcu.readthedocs.org/en/dev/en/support/.
Use one of the two templates below and delete the rest.

8<------------------------ BUG REPORT -----------------------------------------
### Expected behavior

### Actual behavior

### Test code
Provide a minimal and isolated test which will reproduce the problem.
```Lua
-- add code here
```
### NodeMCU version
Which branch are you on? If you know the Git revision then add it here as well.

### Hardware
Describe which ESP8266 device you use and document any special hardware setup 
required to reproduce the problem.

8<------------------------ END BUG REPORT -------------------------------------


8<------------------------ FEATURE REQUEST ------------------------------------
### Missing feature

### Justification
Tell us why you would like to see this feature added.

### Workarounds
Are there any workarounds you currently have in place because the feature is missing?

8<------------------------ END FEATURE REQUEST --------------------------------