| Miguel Ojeda Sandonis | 70e8404 | 2007-02-10 01:44:32 -0800 | [diff] [blame] | 1 | =================================== |
| 2 | cfag12864b LCD Driver Documentation |
| 3 | =================================== |
| 4 | |
| 5 | License: GPLv2 |
| 6 | Author & Maintainer: Miguel Ojeda Sandonis <maxextreme@gmail.com> |
| 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 support one cfag12864b display at time. |
| 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: |
| John Anthony Kazos Jr | be2a608 | 2007-05-09 08:50:42 +0200 | [diff] [blame] | 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 |
| Miguel Ojeda Sandonis | 70e8404 | 2007-02-10 01:44:32 -0800 | [diff] [blame] | 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. |