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Based on kernel version 3.16. Page generated on 2014-08-06 21:36 EST.

1		===================================
2		cfag12864b LCD Driver Documentation
3		===================================
4	
5	License:		GPLv2
6	Author & Maintainer:	Miguel Ojeda Sandonis
7	Date:			2006-10-27
8	
9	
10	
11	--------
12	0. INDEX
13	--------
14	
15		1. DRIVER INFORMATION
16		2. DEVICE INFORMATION
17		3. WIRING
18		4. USERSPACE PROGRAMMING
19	
20	
21	---------------------
22	1. DRIVER INFORMATION
23	---------------------
24	
25	This driver supports a cfag12864b LCD.
26	
27	
28	---------------------
29	2. DEVICE INFORMATION
30	---------------------
31	
32	Manufacturer:	Crystalfontz
33	Device Name:	Crystalfontz 12864b LCD Series
34	Device Code:	cfag12864b
35	Webpage:	http://www.crystalfontz.com
36	Device Webpage:	http://www.crystalfontz.com/products/12864b/
37	Type:		LCD (Liquid Crystal Display)
38	Width:		128
39	Height:		64
40	Colors:		2 (B/N)
41	Controller:	ks0108
42	Controllers:	2
43	Pages:		8 each controller
44	Addresses:	64 each page
45	Data size:	1 byte each address
46	Memory size:	2 * 8 * 64 * 1 = 1024 bytes = 1 Kbyte
47	
48	
49	---------
50	3. WIRING
51	---------
52	
53	The cfag12864b LCD Series don't have official wiring.
54	
55	The common wiring is done to the parallel port as shown:
56	
57	Parallel Port                          cfag12864b
58	
59	  Name Pin#                            Pin# Name
60	
61	Strobe ( 1)------------------------------(17) Enable
62	Data 0 ( 2)------------------------------( 4) Data 0
63	Data 1 ( 3)------------------------------( 5) Data 1
64	Data 2 ( 4)------------------------------( 6) Data 2
65	Data 3 ( 5)------------------------------( 7) Data 3
66	Data 4 ( 6)------------------------------( 8) Data 4
67	Data 5 ( 7)------------------------------( 9) Data 5
68	Data 6 ( 8)------------------------------(10) Data 6
69	Data 7 ( 9)------------------------------(11) Data 7
70	       (10)                      [+5v]---( 1) Vdd
71	       (11)                      [GND]---( 2) Ground
72	       (12)                      [+5v]---(14) Reset
73	       (13)                      [GND]---(15) Read / Write
74	  Line (14)------------------------------(13) Controller Select 1
75	       (15)
76	  Init (16)------------------------------(12) Controller Select 2
77	Select (17)------------------------------(16) Data / Instruction
78	Ground (18)---[GND]              [+5v]---(19) LED +
79	Ground (19)---[GND]
80	Ground (20)---[GND]              E    A             Values:
81	Ground (21)---[GND]       [GND]---[P1]---(18) Vee    - R = Resistor = 22 ohm
82	Ground (22)---[GND]                |                 - P1 = Preset = 10 Kohm
83	Ground (23)---[GND]       ----   S ------( 3) V0     - P2 = Preset = 1 Kohm
84	Ground (24)---[GND]       |  |
85	Ground (25)---[GND] [GND]---[P2]---[R]---(20) LED -
86	
87	
88	------------------------
89	4. USERSPACE PROGRAMMING
90	------------------------
91	
92	The cfag12864bfb describes a framebuffer device (/dev/fbX).
93	
94	It has a size of 1024 bytes = 1 Kbyte.
95	Each bit represents one pixel. If the bit is high, the pixel will
96	turn on. If the pixel is low, the pixel will turn off.
97	
98	You can use the framebuffer as a file: fopen, fwrite, fclose...
99	Although the LCD won't get updated until the next refresh time arrives.
100	
101	Also, you can mmap the framebuffer: open & mmap, munmap & close...
102	which is the best option for most uses.
103	
104	Check Documentation/auxdisplay/cfag12864b-example.c
105	for a real working userspace complete program with usage examples.
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