[問題] 單機RS232傳送問題

看板C_and_CPP (C/C++)作者sgvacr (小兵)時間15年前 (2010/10/10 18:45)推噓4(4推 0噓 13→)

留言17則, 3人參與討論串1/1

( *[1m *[m 為色碼，可以按 Ctrl+V 預覽會顯示的顏色 ) ( 未必需要依照此格式，文章條理清楚即可 ) 1.遇到的問題：我有一台電腦我差了一個USB轉RS232的線所以我現在的RS232是一個COM3的串列阜。我是把RS232的腳位 2,3 接起來短路打算自己送資料自己接資料。我在電腦裡面送出一個字串"I am test string." 2.希望得到的正確結果：按下Esc之後在螢幕上顯示"I get this massage = I am test string." 3.程式跑出來的錯誤結果：按下Esc之後螢幕上顯示"I get this massage =" 4.開發平台： VC++ 2008 in Win xp 5.有問題的code： #include <windows.h> #include <stdio.h> #include <conio.h> //for _getch() and _kbhit(); #include <string> using namespace std; int main(){ HANDLE hComm; DCB dcb; string Temp; //for receiving char inbuff[1024]; DWORD nBytesRead,dwEvent,dwError; COMSTAT cs; int end=FALSE,ky; //for sending const char *SendData; unsigned long lrc, BS; char str1[]="I am a test string."; printf("%s\n",str1); hComm = CreateFile("COM3", GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, 0); if (hComm == INVALID_HANDLE_VALUE){ printf("wrong port connection.\n"); return 0; } GetCommState(hComm,&dcb); dcb.BaudRate = CBR_9600; dcb.ByteSize = 8; dcb.Parity = NOPARITY; dcb.StopBits = ONESTOPBIT; if (!SetCommState(hComm, &dcb)){ printf("setting error.\n"); return 0; } //send Temp=str1; SendData = Temp.c_str(); BS=strlen(SendData); WriteFile(hComm, SendData,BS,&lrc,NULL); //receive ClearCommError(hComm,&dwError,&cs); if (cs.cbInQue > sizeof(inbuff)){ PurgeComm(hComm, PURGE_RXCLEAR); printf("your massage is too big\n"); return 0; } while (!end){ ReadFile(hComm, inbuff,cs.cbInQue, &nBytesRead,NULL); inbuff[cs.cbInQue]='\0'; if (_kbhit()){ if((ky = _getch()) =='\x1B'){ end=TRUE; } } } printf("I get this massage = %s \n",inbuff); return 0; } 麻煩各位大大教一下小新米 ORZ -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.135.96.181