diff options
Diffstat (limited to 'kernel/Documentation/auxdisplay/cfag12864b')
| -rw-r--r-- | kernel/Documentation/auxdisplay/cfag12864b | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/kernel/Documentation/auxdisplay/cfag12864b b/kernel/Documentation/auxdisplay/cfag12864b new file mode 100644 index 000000000..eb7be393a --- /dev/null +++ b/kernel/Documentation/auxdisplay/cfag12864b @@ -0,0 +1,105 @@ + =================================== + cfag12864b LCD Driver Documentation + =================================== + +License: GPLv2 +Author & Maintainer: Miguel Ojeda Sandonis +Date: 2006-10-27 + + + +-------- +0. 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 Documentation/auxdisplay/cfag12864b-example.c +for a real working userspace complete program with usage examples. |