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Changes between Version 3 and Version 4 of wade/debian


Ignore:
Timestamp:
Feb 27, 2009, 3:14:45 PM (17 years ago)
Author:
wade
Comment:

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Unmodified
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  • wade/debian

    v3 v4  
    3636
    3737   有問題可以上IRC channel #dot問問看 http://wiki.debian.org.tw/index.php/IRC
     38
     39== Frame Buffer ==
     40framebuffer 機制其實是 linux kernel 裡的driver interface
     41這個機制其實是模擬顯示卡的功能，讓linux的user可以透過framebuffer device
     42直接對display memory進行讀寫操作
     43我們可以把framebuffer看成是display memory的image(映像)
     44我們可以透過mmap函式把physical address映射到我們應用程式的virtual address
     45如此一來我們就可以直接進行讀寫操作 而這些操作會立即反映在screen上
     46使用者完全不用去理會display memory的physical address
     47這些都由/dev/fb0來完成
     48
     49* http://www.mcublog.com/blog/user1/9450/archives/2006/19773.html