I try to communicate a connecting device via a converter, RS232 to USB with a FTDI chip with QT example "Terminal." After "configure" and "connect", I type some command on the console to send to device. However, nothing new is updated on the console. I even modify the code as

serial->write("*IDN?\n"); // Force Every keyboard event to trigger the write command with char*

in the method "WriteData" within MainWindow.cpp. Still, nothing is shown.

The device has good communication with win XP under BCB control. The OS currently used now is Win 7 or Win 8. But it seems that the command can not be sent to or received from device.

I even change the baudrate setting to 19200 in device, however, the baudrate that detected by Terminal is 9600.

Could anyone help me to figure out what the problem is?