用AVR單片機(jī)設(shè)計(jì)的MP3播放器
功能:
MP3 Player
IDE ATA interface
FAT 32 with long file name support
USB interface
On board power supply (input from 7v to 20v dc)
Bootloader firmware upgradeable via USB port
Infrared bi-directional interface
Remote Control
Back light graphic LCD
worked with only 2x AA batteries
In sleep mode sink less than 1uA (2.5mA in active mode)
5 buttons for easy navigation
Long range (more than 20 feets)
GDI 即圖形設(shè)備界面,是 Windows 最重要的部分之一,它大部分由 GDI32.DLL 庫(kù)中的 API 來(lái)處理,GDI 的主要目的之一是支持與設(shè)備無(wú)關(guān)的圖形編程,對(duì)于 Dos 下的圖形編程,很多人可能“心有余悸”,因?yàn)镻C 中有太多種類的顯示卡,而幾乎每個(gè)顯示卡的處理都是不同的,即使后來(lái)有了 Vesa 編程,我們還是不能全部撇開(kāi)具體的硬件,Windows GDI 使我們對(duì)圖形的編程變得相對(duì)簡(jiǎn)單了很多,由于GDI 是 Windows 最龐大的部分,并不是幾句話能講清楚的,本節(jié)要講的是 Windows 下GDI 的基本處理步驟和簡(jiǎn)單的位圖處理,并沒(méi)有涉及到 Directx 一類的編程。只希望能對(duì)朋友們有所啟發(fā)。
Windows 并不允許程序員訪問(wèn)顯示硬件,它的所有對(duì)屏幕的操作是通過(guò)環(huán)境設(shè)備(dc)來(lái)處理的,屏幕上的每一個(gè)窗口對(duì)應(yīng)一個(gè)dc,你可以把一個(gè)dc 想象成這個(gè)窗口的視頻緩沖區(qū),你對(duì)dc的操作結(jié)果會(huì)反映到屏幕上,在窗口的dc之外,你也可以自己建立dc,這相當(dāng)于建立一個(gè)內(nèi)存中的緩沖區(qū),你對(duì)這個(gè)dc的操作結(jié)果保存在內(nèi)存中。你也可以用 API 在不同的dc之間拷貝數(shù)據(jù),比如說(shuō)你可以在內(nèi)存dc 中先建立好數(shù)據(jù),然后拷貝到窗口的dc中,就相當(dāng)于完成了屏幕的刷新。
This specification defines the Audio Codec ‘97 (AC ‘97) Architecture and Digital Interface (AC-link) specifically
designed for implementing audio and modem I/O functionality in mainstream PC systems. This specification does
not explicitly define the companion AC ‘97 Digital Controller component (sometimes referred to or abbreviated as
dc ‘97), which typically varies in features and implementation, but is AC ‘97 compliant with this specification.