·ITU-T G.729的一個實現(xiàn)例子(包括附錄b的vod檢測等功能)-ITU-T g.729 example, include VOD detect of reference B, etc.文件列表(點擊判斷是否您需要的文件): g729b_v14 .........\acelp_co.c .........\basic_op.c .....
針對目前使用的RS232接口數(shù)字化B超鍵盤存在PC主機啟動時不能設(shè)置BIOS，提出一種PS2鍵盤的設(shè)計方法。基于W78E052D單片機，采用8通道串行A/D轉(zhuǎn)換器設(shè)計了8個TGC電位器信息采集電路，電位器位置信息以鍵盤掃描碼序列形式發(fā)送，正交編碼器信號通過XC9536XL轉(zhuǎn)換為單片機可接收的中斷信號，軟件接收到中斷信息后等效處理成按鍵。結(jié)果表明，在滿足開機可設(shè)置BIOS同時，又可實現(xiàn)超聲特有功能，不需要專門設(shè)計驅(qū)動程序，接口簡單，成本低。
Abstract: Aiming at the problem of the digital ultrasonic diagnostic imaging system keyboard with RS232 interface currently used couldn?蒺t set the BIOS when the PC boot， this paper proposed a design method of PS2 keyboards. Based on W78E052D microcontroller，designed eight TGC potentiometers information acquisition circuit with 8-channel serial A/D converter， potentiometer position information sent out with keyboard scan code sequentially.The control circuit based on XC9536 CPLD is used for converting the mechanical actions of the encoders into the signals that can be identified by the MCU， software received interrupt information and equivalently treatmented as key. The results show that the BIOS can be set to meet the boot， ultrasound specific functionality can be achieved at the same time， it does not require specially designed driver，the interface is simple and low cost.
介紹了用單片機C 語言實現(xiàn)無功補償中電容組循環(huán)投切的基本原理和算法，并舉例說明。關(guān)鍵詞：循環(huán)投切;C51;無功補償中圖分類號： TM76 文獻標識碼： BAbstract: This paper introduces the aplication of C51 in the controlling of capacitorsuits cycle powered to be on and off in reactive compensation.it illustrate thefondamental principle and algorithm with example.Key words: cycle powered to be on and off; C51; reactive compensation
為提高功率因數(shù)，往往采用補償電容的方法來實現(xiàn)。而電容器的容量是由實時功率因數(shù)與標準值進行比較來決定的，實時功率因數(shù)小于標準值時，需投入電容組，實時功率因數(shù)大于標準值時，則需切除電容組。投切方式的不合理，會對電容器造成損壞，現(xiàn)有的控制器多采用“順序投切”方式，在這種投切方式下排序在前的電容器組，先投后切；而后面的卻后投先切。這不僅使處于前面的電容組經(jīng)常處于運行狀態(tài)，積累熱量不易散失，影響其使用壽命，而且使后面的投切開關(guān)經(jīng)常動作，同樣減少壽命。合理的投切方式應為“循環(huán)投切”。這種投切方式使先投入的運行的電容組先退出，后投的后切除，從而使各組電容及投切開關(guān)使用機率均等，降低了電容組的平均運行溫度，減少了投切開關(guān)的動作次數(shù)，延長了其使用壽命。
