通過比較各種隔離數(shù)字通信的特點和應(yīng)用范圍,指出塑料光纖在隔離數(shù)字通信中的優(yōu)勢。使用已經(jīng)標準化的TOSLINK接口,有利于節(jié)省硬件開發(fā)成本和簡化設(shè)計難度。給出了塑料光纖的硬件驅(qū)動電路,說明設(shè)計過程中的注意事項,對光收發(fā)模塊的電壓特性和頻率特性進行全面試驗,并給出SPI口使用塑料光纖隔離通信的典型應(yīng)用電路圖。試驗結(jié)果表明,該設(shè)計可為電力現(xiàn)場、電力電子及儀器儀表的設(shè)計提供參考。
Abstract:
y comparing characteristics and applications area of various isolated digital communications, this article indicates advantages of plastic optical fiber in isolated digital communications. Using the standardized TOSLINK interface, it helps to control costs and difficulty in hardware development and design. Then it gives the hardware driver circuit of plastic optical fiber module, explains the noticed details in design process, gives results on the basis of the optical transceiver module voltage characteristics and frequency characteristics tests. Finally,it gives typical application circuit of the SPI communication port by using plastic optical fiber isolation .The results show that this design can be referenced for the power field, power electronics and instrumentation design.
本書第二部分講述的是在Wi n 3 2平臺上的Wi n s o c k編程。對于眾多的基層網(wǎng)絡(luò)協(xié)議,
Wi n s o c k是訪問它們的首選接口。而且在每個Wi n 3 2平臺上,Wi n s o c k都以不同的形式存在著。
Wi n s o c k是網(wǎng)絡(luò)編程接口,而不是協(xié)議。它從U n i x平臺的B e r k e l e y(B S D)套接字方案借鑒了
許多東西,后者能訪問多種網(wǎng)絡(luò)協(xié)議。在Wi n 3 2環(huán)境中,Wi n s o c k接口最終成為一個真正的
“與協(xié)議無關(guān)”接口,尤其是在Winsock 2發(fā)布之后。
PIECEWISE_EVAL: evaluates a piecewise function of x
usage: y = PIECEWISE_EVAL(x,breakpoints,funs)
arguments (input)
x - vector or array of points to evaluate though the function
breakpoints - list of n breakpoints, -inf and +inf are implicitly
/*
* EULER S ALGORITHM 5.1
*
* TO APPROXIMATE THE SOLUTION OF THE INITIAL VALUE PROBLEM:
* Y = F(T,Y), A<=T<=B, Y(A) = ALPHA,
* AT N+1 EQUALLY SPACED POINTS IN THE INTERVAL [A,B].
*
* INPUT: ENDPOINTS A,B INITIAL CONDITION ALPHA INTEGER N.
*
* OUTPUT: APPROXIMATION W TO Y AT THE (N+1) VALUES OF T.
*/