替代加密:
A B C D E F G H I J K L M N O P Q R S T U V W 密文
Y Z D M R N H X J L I O Q U W A C B E G F K P 明文
X Y Z
T S V
I HAVE A DREAM！#
密文？？
用ARM編程實(shí)現(xiàn)替代加密。
本書第二部分講述的是在Wi n 3 2平臺(tái)上的Wi n s o c k編程。對(duì)于眾多的基層網(wǎng)絡(luò)協(xié)議，
Wi n s o c k是訪問(wèn)它們的首選接口。而且在每個(gè)Wi n 3 2平臺(tái)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(tái)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(wèn)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(gè)真正的
“與協(xié)議無(wú)關(guān)”接口，尤其是在Winsock 2發(fā)布之后。
/*
* 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.
*/
performs one of the matrix-vector operations y := alpha*A*x + beta*y, or y := alpha*A *x + beta*y, where alpha and beta are scalars, x and y are vectors and A is an
m by n matrix
Embest S3C44B0X Evaluation Board
RTC Test Example
RTC Check(Y/N)? y
Set Default Time at 2004-12-31 FRI 23:59:59
Set Alarm Time at 2005-01-01 00:00:01
... RTC Alarm Interrupt O.K. ...
Current Time is 2005-01-01 SAT
00:00:01
RTC Working now. To set date(Y/N)? y
Current date is (2005,01,01, SAT). input new date (yy-mm-dd w): 5-2-23 3
Current date is: 2005-02-23 WED
RTC Working now. To set time(Y/N)? y
Current time is (00:00:21). To set time(hh:mm:ss): 19:32:5
Current Time is 2005-02-23 WED
19:32:
