AJAX web interface for BSB_lan project

Benefits:

• Saving flash memory for future features and functions (more than 39kB for German language and more than 150kB for multi-byte alphabets). You can still use Arduino Mega with interface board v.2 (deprecated, last official release with v.2 support is 0.44 but it works with 2.x). You do not need Arduino Due or ESP32 boards, but it certainly supported too.
• Modern interface (Oh, yeah)
• More comfort experience on mobile device.
• Easy for customization and expansion.

Disadvantages:

• First run will be slower because SD card and network interface throughput is low (50~70kB/s for Mega and LAN 5100).
• Need more browser RAM (up to ~20MB per interface instance). Category caching can be disabled for decreasing memory consumption.

Requirements

• Hardware: same as for BSB_lan project. SD card needed.
• Software: modern browser with HTML5, JavaScript, CSS2(3?) support. Tested on Firefox, Google Chrome, Yandex browser (Chromium core).

How to install/run.

• Patch BSB_lan.ino by patch.
• Copy langtoajax.pl to "localization" directory.
• Run langtoajax.pl. This script creating these files:

1. LANG_C.h - language-independed text resources definitions.
2. UNDEF_LANG_C.h
3. lang_*.js - JavaScript files with localizations.
4. lang_*.js.gz - gzipped JavaScript files with localizations (need gzip).

All above was included in BSB_lan project, so you do not need do anything.

• (For BSB-LAN version 2.x since 06.12.2020) You can enable #define I_WILL_USE_EXTERNAL_INTERFACE in config file if you want save some flash memory (~7 kB). /D command is equal /datalog.txt and /DG included into ajax.html.
• Edit BSB_lan_config.h:

1. add or uncomment #define WEBSERVER and #define JSONCONFIG (JSONCONFIG is available in BSB-LAN since 24.12.2020)
2. change LANG from DE to C

• Build sketch and flash it into Arduino.
• Copy ajax.html, settings.js to root of SD card.
• Copy from BSB-lan project localization\www\languages.js to root of SD card.
• Copy from BSB-lan project localization\www\lang_*.js and localization\www\lang_*.js.gz files to root of SD card.
• Copy from BSB-lan project src/d3.v3.min.js to root of SD card.
• You can change settings by editing file settings.js
• Insert SD card into Arduino and start it.
• Open http://yourbsblandeviceaddress/ajax.html in your browser. Note: you can rename ajax.html to index.html and just type http://yourbsblandeviceaddress/ to start AJAX interface.

Features:

• Pure JavaScript (excl. D3 library for charts drawing).
• Language autodetection.
• Language switching on the fly.
• Asynchronous data loading/updating.
• Switching between categories without page reloading.
• Configuration save/restore (very slow due BSB protocol limitation).
• D3 library can be placed on SD card for standalone installations (without connection to Internet).
• You can build list of unsupported parameters and save it to SD card with name 'notsupported.js'. Parameters in the list are never requested, except for the exception list building function.
• Icons with links to external resources are hidden on small screens.

At this point time interface looks highly similar original bsb_lan.