Introduction
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Fork of https://github.com/crystalfontz/cfa_735_simple 
Original author http://rob.emanuele.us/ 
Most updated version git://git.assembla.com/mbvideo.lcd.git
Support separate bootloader and application, allows remote upgrade of the firmware.

The firmware running on the LCD provides partially compatible with original CrystalFontz API. 
There are 35 commands in total documented in the CFA-735-xxx-KT_Data_Sheet. 
This part of README file covers extensions for the command set and changes in the command set.

Not supported commands:

*  2 (0x02): Write User Flash Area - not supported
*  3 (0x03): Read User Flash Area - not supported
*  4 (0x04): Store Current State As Boot State - not supported
*  5 (0x05): Reset Functions - not supported
*  16 (0x10): Set Up Fan Reporting (FBSCAB required) - not supported
*  17 (0x11): Set Fan Power (FBSCABrequired)
*  18 (0x12): Read DOW Device Information (FBSCAB required)
*  19 (0x13): Set Up Temperature Reporting (FBSCAB required)
*  20 (0x14): Arbitrary DOW Transaction (FBSCAB required)
*  25 (0x19): Set Fan Power Fail-Safe (FBSCAB required)
*  26 (0x1A): Set Fan Tachometer Glitch Filter (FBSCAB required)
*  27 (0x1B): Query Fan Power & Fail-Safe Mask (FBSCAB required)
*  28 (0x1C): Set ATX Power Switch Functionality
*  29 (0x1D): Enable/Disable and Reset the Watchdog

Modified commands:


*  9 (0x09): Set LCD Special Character Data

First byte of the payload - index of the special character. The legal value for the index is 0-255.
The command will store the characters in the RAM

*  31 (0x1F): Send Data to LCD
Payload bytes [2-21] contains codes of the characters. 
The default characters table follows the Figure 25, but instead of English ABC there are Cyrillic letters. 
For encoding in the current source code see http://en.wikipedia.org/wiki/CP866


HowTo 
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 Prerequisites.
   
*  STMLink v2 or similar
*  Open OCD
*  ST-LINK In-circuit debugger and programmer for STM8 and STM32 MCUs  (download from http://www.st.com/internet/evalboard/product/219866.jsp)
*  Linux, Windows
*  Optional LCDProc

  Preparations.
  
1. Connect JTAG
2. Bring up the ST-LINK (runs only Windows)
3. Keep the reset pin on the H1 connector low. Connect the ping to the ground if needed, but do not solder.
4. From ST-LINK utility reset the card and disable write protect (menu options byte)
5. Erase the FLASH (this is probably a good idea to save the original LCD firmware first)

The card is ready for the custom firmware

  Compilation and programming
   
1. Open the JTAG device using OpenOCD: sudo ../src/openocd  -f board/stm32vldiscovery.cfg
2. Open telnet: telnet localhost 4444 
3. Compile the firmware make -C ./src all
4. In the telnet: reset halt;flash write_image erase ./cfa735.elf.hex;reset
5. In the telnet: reset 
6. Compile CFA735 tests: cd test; make
7. Run the test: ./example-635 /dev/ttyACM0 115200. You should see 4 text lines on the LCD screen