Transferred node module documentation.

docs/en/modules/node.md

@@ -1,4 +1,6 @@
 # node Module
+The node module provides access to system-level features such as sleep, restart and various info and IDs.
+
 ## node.restart()
 
 Restarts the chip.
@@ -54,4 +56,282 @@ node.dsleep(1000000, 4)
 --set sleep option only
 node.dsleep(nil,4)
 ```
-___
+___
+## node.info()
+
+Returns NodeMCU version, chipid, flashid, flash size, flash mode, flash speed.
+
+####Syntax
+`node.info()`
+
+####Parameters
+`nil`
+
+####Returns
+ - `majorVer` (number)
+ - `minorVer` (number)
+ - `devVer` (number)
+ - `chipid` (number)
+ - `flashid` (number)
+ - `flashsize` (number)
+ - `flashmode` (number)
+ - `flashspeed` (number)
+
+####Example
+
+```lua
+    majorVer, minorVer, devVer, chipid, flashid, flashsize, flashmode, flashspeed = node.info()
+    print("NodeMCU "..majorVer.."."..minorVer.."."..devVer)
+```
+___
+## node.chipid()
+
+Returns the ESP chip ID.
+
+####Syntax
+`node.chipid()`
+
+####Parameters
+`nil`
+
+####Returns
+number:chip ID
+
+####Example
+
+```lua
+    id = node.chipid();
+```
+___
+## node.flashid()
+Returns the flash chip ID.
+
+####Syntax
+`node.flashid()`
+
+####Parameters
+`nil`
+
+####Returns
+number:flash ID
+
+####Example
+
+```lua
+    flashid = node.flashid();
+```
+___
+## node.heap()
+Returns the current available heap size in bytes. Note that due to fragmentation, actual allocations of this size may not be possible.
+
+####Syntax
+`node.heap()`
+
+####Parameters
+`nil`
+
+####Returns
+number: system heap size left in bytes
+
+####Example
+
+```lua
+    heap_size = node.heap();
+```
+___
+## node.key() --deprecated
+
+Define action to take on button press (on the old devkit 0.9), button connected to GPIO 16.
+
+This function is only available if the firmware was compiled with DEVKIT_VERSION_0_9 defined.
+
+
+####Syntax
+`node.key(type, function)`
+
+####Parameters
+  - `type`: type is either string "long" or "short". long: press the key for 3 seconds, short: press shortly(less than 3 seconds)
+  - `function`: user defined function which is called when key is pressed. If nil, remove the user defined function. Default function: long: change LED blinking rate,  short: reset chip
+
+####Returns
+`nil`
+
+####Example
+```lua
+    node.key("long", function() print('hello world') end)
+```
+####See also
+  - `node.led()`
+___
+## node.led() --deprecated
+
+Set the on/off time for the LED (on the old devkit 0.9), with the LED connected to GPIO16, multiplexed with `node.key()`.
+
+This function is only available if the firmware was compiled with DEVKIT_VERSION_0_9 defined.
+
+####Syntax
+`node.led(low, high)`
+
+####Parameters
+  - `low`: LED off time, LED keeps on when low=0. Unit: milliseconds, time resolution: 80~100ms<br />
+  - `high`: LED on time. Unit: milliseconds, time resolution: 80~100ms
+
+####Returns
+`nil`
+
+####Example
+
+```lua
+    -- turn led on forever.
+    node.led(0)
+```
+
+####See also
+  - `node.key()`
+___
+## node.input()
+
+Submit a string to the Lua interpreter. Similar to `pcall(loadstring(str))`, but without the single-line limitation.
+
+!!! note "Note:"
+
+  This function only has an effect when invoked from a callback. Using it directly on the console **does not work**.
+
+####Syntax
+`node.input(str)`
+
+####Parameters
+  - `str`: Lua chunk
+
+####Returns
+`nil`
+
+####Example
+
+```lua
+    sk:on("receive", function(conn, payload) node.input(payload) end)
+```
+
+####See also
+  - `node.output()`
+___
+## node.output()
+
+Redirects the Lua interpreter output to a callback function. Optionally also prints it to the serial console.
+
+!!! note "Note:"
+
+  Do **not** attempt to `print()` or otherwise induce the Lua interpreter to produce output from within the callback function. Doing so results in infinite recursion, and leads to a watchdog-triggered restart.
+
+####Syntax
+`node.output(output_fn, serial_debug)`
+
+####Parameters
+  - `output_fn(str)`: a function accept every output as str, and can send the output to a socket (or maybe a file).
+  - `serial_debug`: 1 output also show in serial. 0: no serial output.
+
+####Returns
+`nil`
+
+####Example
+
+```lua
+    function tonet(str)
+      sk:send(str)
+    end
+    node.output(tonet, 1)  -- serial also get the lua output.
+```
+
+```lua
+    -- a simple telnet server
+    s=net.createServer(net.TCP)
+    s:listen(2323,function(c)
+       con_std = c
+       function s_output(str)
+          if(con_std~=nil)
+             then con_std:send(str)
+          end
+       end
+       node.output(s_output, 0)   -- re-direct output to function s_ouput.
+       c:on("receive",function(c,l)
+          node.input(l)           -- works like pcall(loadstring(l)) but support multiple separate line
+       end)
+       c:on("disconnection",function(c)
+          con_std = nil
+          node.output(nil)        -- un-regist the redirect output function, output goes to serial
+       end)
+    end)
+```
+####See also
+  - `node.input()`
+___
+## node.readvdd33() --deprecated, moved to adc.readvdd33()
+####See also
+  - `adc.readvdd33()`
+___
+## node.compile()
+
+Compile a Lua text file into Lua bytecode, and save it as .lc file.
+
+####Syntax
+`node.compile(filename)`
+
+####Parameters
+  - `filename`: name of Lua text file
+
+####Returns
+`nil`
+
+####Example
+```lua
+  file.open("hello.lua","w+")
+  file.writeline([[print("hello nodemcu")]])
+  file.writeline([[print(node.heap())]])
+  file.close()
+
+  node.compile("hello.lua")
+  dofile("hello.lua")
+  dofile("hello.lc")
+```
+___
+## node.setcpufreq()
+
+Change the working CPU Frequency.
+
+####Syntax
+`node.setcpufreq(speed)`
+
+####Parameters
+  - `speed`: `node.CPU80MHZ` or `node.CPU160MHZ`
+
+####Returns
+number:target CPU Frequency
+
+####Example
+
+```lua
+    node.setcpufreq(node.CPU80MHZ)
+```
+___
+## node.restore()
+
+Restore system configuration to defaults. Erases all stored WiFi settings, and resets the "esp init data" to the defaults. This function is intended as a last-resort without having to reflash the ESP altogether.
+
+This also uses the SDK function `system_restore()`, which doesn't document precisely what it erases/restores.
+
+####Syntax
+`node.restore()`
+
+####Parameters
+`nil`
+
+####Returns
+`nil`
+
+####Example
+
+```lua
+    node.restore()
+    node.restart() -- ensure the restored settings take effect
+```
+___