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+===================================
+cfag12864b LCD Driver Documentation
+===================================
+
+:License: GPLv2
+:Author & Maintainer: Miguel Ojeda <ojeda@kernel.org>
+:Date: 2006-10-27
+
+
+
+.. INDEX
+
+ 1. DRIVER INFORMATION
+ 2. DEVICE INFORMATION
+ 3. WIRING
+ 4. USERSPACE PROGRAMMING
+
+1. Driver Information
+---------------------
+
+This driver supports a cfag12864b LCD.
+
+
+2. Device Information
+---------------------
+
+:Manufacturer: Crystalfontz
+:Device Name: Crystalfontz 12864b LCD Series
+:Device Code: cfag12864b
+:Webpage: http://www.crystalfontz.com
+:Device Webpage: http://www.crystalfontz.com/products/12864b/
+:Type: LCD (Liquid Crystal Display)
+:Width: 128
+:Height: 64
+:Colors: 2 (B/N)
+:Controller: ks0108
+:Controllers: 2
+:Pages: 8 each controller
+:Addresses: 64 each page
+:Data size: 1 byte each address
+:Memory size: 2 * 8 * 64 * 1 = 1024 bytes = 1 Kbyte
+
+
+3. Wiring
+---------
+
+The cfag12864b LCD Series don't have official wiring.
+
+The common wiring is done to the parallel port as shown::
+
+ Parallel Port cfag12864b
+
+ Name Pin# Pin# Name
+
+ Strobe ( 1)------------------------------(17) Enable
+ Data 0 ( 2)------------------------------( 4) Data 0
+ Data 1 ( 3)------------------------------( 5) Data 1
+ Data 2 ( 4)------------------------------( 6) Data 2
+ Data 3 ( 5)------------------------------( 7) Data 3
+ Data 4 ( 6)------------------------------( 8) Data 4
+ Data 5 ( 7)------------------------------( 9) Data 5
+ Data 6 ( 8)------------------------------(10) Data 6
+ Data 7 ( 9)------------------------------(11) Data 7
+ (10) [+5v]---( 1) Vdd
+ (11) [GND]---( 2) Ground
+ (12) [+5v]---(14) Reset
+ (13) [GND]---(15) Read / Write
+ Line (14)------------------------------(13) Controller Select 1
+ (15)
+ Init (16)------------------------------(12) Controller Select 2
+ Select (17)------------------------------(16) Data / Instruction
+ Ground (18)---[GND] [+5v]---(19) LED +
+ Ground (19)---[GND]
+ Ground (20)---[GND] E A Values:
+ Ground (21)---[GND] [GND]---[P1]---(18) Vee - R = Resistor = 22 ohm
+ Ground (22)---[GND] | - P1 = Preset = 10 Kohm
+ Ground (23)---[GND] ---- S ------( 3) V0 - P2 = Preset = 1 Kohm
+ Ground (24)---[GND] | |
+ Ground (25)---[GND] [GND]---[P2]---[R]---(20) LED -
+
+
+4. Userspace Programming
+------------------------
+
+The cfag12864bfb describes a framebuffer device (/dev/fbX).
+
+It has a size of 1024 bytes = 1 Kbyte.
+Each bit represents one pixel. If the bit is high, the pixel will
+turn on. If the pixel is low, the pixel will turn off.
+
+You can use the framebuffer as a file: fopen, fwrite, fclose...
+Although the LCD won't get updated until the next refresh time arrives.
+
+Also, you can mmap the framebuffer: open & mmap, munmap & close...
+which is the best option for most uses.
+
+Check samples/auxdisplay/cfag12864b-example.c
+for a real working userspace complete program with usage examples.