USB转232 波特率设置问题

Question

你可以打开DCD的波特率枚举值处看看，是否包含对应的后两个设置

Answer 1

这是执行GetCommState(m_hComm, &m_dcb)时调试窗口的值，
- m_dcb {DCBlength=28 BaudRate=115200 fBinary=1 ...} _DCB
DCBlength 28 unsigned long
BaudRate 115200 unsigned long
fBinary 1 unsigned long
fParity 0 unsigned long
fOutxCtsFlow 0 unsigned long
fOutxDsrFlow 0 unsigned long
fDtrControl 1 unsigned long
fDsrSensitivity 0 unsigned long
fTXContinueOnXoff 0 unsigned long
fOutX 0 unsigned long
fInX 0 unsigned long
fErrorChar 0 unsigned long
fNull 0 unsigned long
fRtsControl 1 unsigned long
fAbortOnError 0 unsigned long
fDummy2 0 unsigned long
wReserved 0 unsigned short
XonLim 2048 unsigned short
XoffLim 512 unsigned short
ByteSize 8 '' unsigned char
Parity 0 unsigned char
StopBits 0 unsigned char
XonChar 17 '' char
XoffChar 19 '' char
ErrorChar 0 char
EofChar 0 char
EvtChar 113 'q' char
wReserved1 0 unsigned short
这是执行SetCommState(m_hComm, &m_dcb)时调试窗口的值，
+ &m_dcb 0x0013fed0 {DCBlength=28 BaudRate=250000 fBinary=1 ...} _DCB *
databits 8 unsigned int
- m_dcb {DCBlength=28 BaudRate=250000 fBinary=1 ...} _DCB
DCBlength 28 unsigned long
BaudRate 250000 unsigned long
fBinary 1 unsigned long
fParity 0 unsigned long
fOutxCtsFlow 0 unsigned long
fOutxDsrFlow 0 unsigned long
fDtrControl 1 unsigned long
fDsrSensitivity 0 unsigned long
fTXContinueOnXoff 0 unsigned long
fOutX 0 unsigned long
fInX 0 unsigned long
fErrorChar 0 unsigned long
fNull 0 unsigned long
fRtsControl 1 unsigned long
fAbortOnError 0 unsigned long
fDummy2 0 unsigned long
wReserved 0 unsigned short
XonLim 2048 unsigned short
XoffLim 512 unsigned short
ByteSize 8 '' unsigned char
Parity 0 unsigned char
StopBits 0 unsigned char
XonChar 17 '' char
XoffChar 19 '' char
ErrorChar 0 char
EofChar 0 char
EvtChar 113 'q' char
wReserved1 0 unsigned short只有波特率发生了变化，还是报错

Answer 2

查MSDN看DCB里的波特率是不是有超过115200以上的参数，就象1楼说的，另外，原先的计算机也不支持超过115200的波特率，虽然USB转232支持

Answer 3

这是我在《winbase.h》中看到，希望能帮到你：
//
// Baud rates at which the communication device operates
//
#define CBR_110             110
#define CBR_300             300
#define CBR_600             600
#define CBR_1200            1200
#define CBR_2400            2400
#define CBR_4800            4800
#define CBR_9600            9600
#define CBR_14400           14400
#define CBR_19200           19200
#define CBR_38400           38400
#define CBR_56000           56000
#define CBR_57600           57600
#define CBR_115200          115200
#define CBR_128000          128000
#define CBR_256000          256000