FW for ESP8266 used with 3D printer

##Description
Thanks to @disneysw for bringing this module idea
Thanks to @lkarlslund for suggestion about independant reset using GPIO2

Have a bridge configurable by web (implemented) and optionally by printer (not yet implemented)
Have a front end to know what is the wifi status (implemented) or know what is the print status (not yet implemented) - this part can be optional and removed by compilation directive if no need

Should be compatible with reprap printer (Marlin FW/Repetier FW) as soon as you can make both serial to communicate.

current release is v0.4-beta.1: https://github.com/luc-github/ESP8266/releases/tag/v0.4-beta.1, need to use at least staging version 1.6.5-1160-gef26c5f

master may not work unless you use the latest code of https://github.com/esp8266/arduino due to delay between PR integration in staging/stable versions

##Hardware connection
--Use GPIO2 to ground to reset all settings in hard way - 2-6 sec after boot / not before!! Set GPIO2 to ground before boot change boot mode and go to special boot that do not reach FW. Currently boot take 10 sec - giving 8 seconds to connect GPIO2 to GND and do an hard recovery for settings
--Use GPIO0 to ground to be in update mode
--Use a switch to reset/disable module


For Davinci Board:

##Development
Currently using Arduino IDE 1.6.5 with the esp8266 module from board manager added from github.com/esp8266/Arduino
using relased version (http://arduino.esp8266.com/package_esp8266com_index.json)
and staging version (http://arduino.esp8266.com/staging/package_esp8266com_index.json)

Additionnaly:
--Use minimal css from http://getbootstrap.com/examples/theme/

##Flash the Module
*Tools:
--Use IDE to upload directly (latest version of board manager module generate one binary)

*Connection --Connect GPIO0 to ground to be in update mode

##Web configuration
*Wifi Mode : Access point / Client station
*IP Generation: DHCP/Static IP
*IP/MASK/GATEWAY for static data
*Baud Rate for serial (supported : 9600, 19200, 38400, 57600, 115200, 230400, 250000)
*web port and data port

##Default Configuration
Default Settings:
AP:ESP8266
PW:12345678
Authentification: WPA
Mode: g (n is not supported by AP, just by STA)
channel: 11
AP: visible
Sleep Mode: Modem
IP Mode: Static IP
IP: 192.168.0.1
Mask: 255.255.255.0
GW:192.168.0.1
Baud rate: 9600
Web port:80
Data port: 8888
Web Page refresh: 3 secondes

These are the pages defined using template:
Home page :

System Configuration Page:


Access Point Configuration Page:


Client Configuration Page:


Printer Status Page for 64K SPIFFS, due to limited space available no fancy:


Printer Status Page for more than 64K SPIFFS, fancy one:


Extra Settings Page, for web UI and for printer:


the template files are stored on SPIFFS:

and uploaded using IDE
The list of keywords can be find here : https://github.com/luc-github/ESP8266/blob/master/keywords.txt
Any files on SPIFFS can be called on web interface without having the path hard coded - this give more flexibility, favicon.ico is a good example of it.
So UI is kind of separated from FW which allow easier modifications. For this a light file manager is available in extra settings page, it allows to upload/download/delete files. as SPIFFS is flat filesystem no directory management is necessary so it is very simple.

Additionally 404.tpl (the page not found) and restart.tpl(restart page when applying changes) are not mandatory, a fail safe version is embeded if they are not present.

Currently, I tested on ESP01 using 64K SPIFFS ( please use data directory content accordingly due to space limitation) and NodeMCU 1.0 1M SPIFFS.

##Protocol for discovery
*mDNS : on Station mode only with bonjour installed on computer (done)
*SSDP : on Station and AP mode (done)
*Captive portal : on AP mode only (not yet functionnal)

##Commands/msg from/to serial(not fully implemented):
*from module to printer by serial communication
-M117 [Message], Error/status message from module (done)
-Send Wifi settings [AP/STATION,SSID,DHC/STATIC,IP,MASK,GW,STATUS,MAC ADDRESSS, BAUD?], ]Module configuration without password

*from host to printer on port 8888 (implemented) - bridge from TCP/IP to Serial and vice-versa (done)

*from printer/host to module (not fully implemented)
-request configuration/status
-set AP/STATION,SSID,PASSSWORD,DHC/STATIC,IP,MASK,GW,BAUD from serial -restart module from host/printer: [ESP888]RESTART
-Get IP (only printer see answer): [ESP111]M117
-reset EEPROM and restart: [ESP444]RESET
-display EEPROM content: [ESP444]CONFIG
-go to safe mode without restart: [ESP444]SAFEMODE
-SSID: [ESP100]
-Password: [ESP101]
-Station mode: [ESP103]STA
-AP mode: [ESP103]AP
-IP Static: [ESP103]STATIC
-IP DHCP: [ESP103]DHCP

##Front End (implemented) --Display printer status (done)
--Display temperatures (done)
--Display positions/flow/speed (done)
--Display print progress if any (done)
--List SDCard Content (done)
--Launch a Print (done)
--Stop/Pause a Print (done)
--Emergency Stop (done)
--Jog control / custom commands (done)

##TODO
-- Close open topics
-- Do testing (a lot)
-- UI Improvement
--Printer EEPROM management (Canceled/Postponed for next stage)

more to come