[Lcdproc] support for the ft245B in hd44780-ftdi

[Ismail Ibrahim]

hello all

To make thing simple, I modified the driver this way.
4 bit driver still lack of backlight control.Hope somebody try to implement it.

Here are some documentation of the new ftdi driver
//simple documentation

HD44780 - ftdi

The FTDI chip support bit bang mode in 8 bits.
Some chip even have dual controller so it doubles to 16 bits.
						
		    FTDI chip					
-----------------------------------------------------------------------					
|       Single Channel          |       Dual Channel    |
|-------------------------------- ------|------------------------------|
| FT245x x={BQ,BL,BM,R} | FT2232x x={D,L,C}  |
| FT232x x={BQ,BL,BM,R}	|	                        |	
-----------------------------------------------------------------------

=================
FTDI Driver mode
=================
8 Bit mode (Default).
The HD44780 is driven in 8 bits using the first channel(A)
and using the second channel(B) for controlling the RS,RW,E and backlight.

4 Bit mode (need to define ftdi_mode=4 in LCDd.conf)				
Requires only one channel of the bit bang mode.The HD44780 will be
driven in 4 bits mode.
4 bits of the bit bang mode are for data and other 3 will be used for RS,RW,E.
The extra 1 bit can be use for controlling backlight,key..etc

======
Pinout
======

	FTDI Bit-Bang Pinout
-----------------------------------------------------------
| Bit-Bang | FT245x | FT232x | FT2232x   |
-----------------------------------------------------------
|   Data0   |    D0     |    TXD   | *DBUS0   |
|   Data1   |    D1     |    RXD   | *DBUS1  |
|   Data2   |    D2     |    RTS   | *DBUS2  |
|   Data3   |    D3     |    CTS   | *DBUS3  |
|   Data4   |    D4     |    DTR   | *DBUS4  |
|   Data5   |    D5     |    DSR   | *DBUS5 |
|   Data6   |    D6     |    DCD   | *DBUS6 |
|   Data7   |    D7     |      RI     | *DBUS7 |
-----------------------------------------------------------

for FT2232x, * is the channel(A/B)

==============
Wiring example
==============

I.8 Bit Wiring(Dual Channel)

----------------------------------------------------------------------------
|             Channel A        ||          Channel B            |
----------------------------------------------------------------------------
|     Bit-Bang  | HD44780  ||   Bit-Bang    | HD44780  |
----------------------------------------------------------------------------
| Data0(0x01) |     D0       || Data0(0x01) |   RS         |
| Data1(0x02) |     D1       || Data1(0x02) |   RW        |
| Data2(0x04) |     D2       || Data2(0x04) |   EN         |
| Data3(0x08) |     D3       || Data3(0x08) |   BL          |
| Data4(0x10) |     D4       || Data4(0x10) | Not Use    |
| Data5(0x20) |     D5       || Data5(0x20) | Not Use    |
| Data6(0x40) |     D6       || Data5(0x20) | Not Use    |
| Data7(0x80) |     D7       || Data5(0x20) | Not Use    |
----------------------------------------------------------------------------

no need to define anything.The driver is default to this set of wiring

II.4 Bit Wiring(Single Channel)

--------------------------------------
|     Bit-Bang  | HD44780  |
--------------------------------------
| Data0(0x01) |     D4       |
| Data1(0x02) |     D5       |
| Data2(0x04) |     D6       |
| Data3(0x08) |     D7       |
| Data4(0x10) |     EN      |
| Data5(0x20) |     RW     |
| Data6(0x40) |     RS      |
| Data7(0x80) | Not Use   |
-------------------------------------

For this set of wiring schem, we need to define
  ftdi_mode=4
  ftdi_line_RS=0x40
  ftdi_line_RW=0x20
  ftdi_line_EN=0x10
in LCDd.conf

And of course,If you wire your LCD in the different way,
just define the appropriate Databit corresponding to RS,RW,EN
//

Some wiring pictures in http://pixca.net/2008/01/30/hd44780-ftdi-usb-lcd/

Thanks