If we have two individually sorted vectors "a" and "b" but they are not sorted with respect to each other and we want to merge them into vector "c" such that "c" is also a sorted vector. Then c=mergesorted(a,b) can be used.
1. 下列說法正確的是 ( )
A. Java語言不區分大小寫
B. Java程序以類為基本單位
C. JVM為Java虛擬機JVM的英文縮寫
D. 運行Java程序需要先安裝JDK
2. 下列說法中錯誤的是 ( )
A. Java語言是編譯執行的
B. Java中使用了多進程技術
C. Java的單行注視以//開頭
D. Java語言具有很高的安全性
3. 下面不屬于Java語言特點的一項是( )
A. 安全性
B. 分布式
C. 移植性
D. 編譯執行
4. 下列語句中,正確的項是 ( )
A . int $e,a,b=10
B. char c,d=’a’
C. float e=0.0d
D. double c=0.0f
為解決當前計算機串行通訊接口只有USB,難以滿足舊型號設備或某些單片機要求RS232通訊的問題,設計出兩款RS232/USB電路。采用CH341A與MAX223集成電路芯片構建標準9線RS232/USB通用接口轉換器,無需編程。采用CH341A與PIC16F877A構建單片機與計算機之間的USB通訊電路,軟件遵循RS232通訊協議,硬件進行電平轉換。實際使用表明,這兩款產品與計算機端Windows 操作系統下的串口應用程序完全兼容,且通訊過程中無握手失敗現象。
Abstract: To solve the problem that current computer serial communication only with USB interface can not satisfy with the old type equipments or MCU to communicate with RS232, two kinds of RS232/USB circuit were designed.CH341A and MAX223 integrated circuit chips were used to create a standard 9-line RS232/USB universal interface convertor without programme. CH341A and PIC16F877A chips were adopted to build the USB communication circuit between computers and MCU. The software follows RS232 communication protocol, and the hardware converts electrical levels. Actual practices indicate that the two manufactures are compatible with serial application program of Windows operation system completely,and get avoid of handshake lost.