Now I am use serial port(COM1) to control a motor,and use VISA in lv.I am new to program serial port . I hope someone tell me how to send the command "?R"&CHR$(13) to COM1 .I can send "?R" with Write VISA.vi , but I do not know how to express CHR$(13). Someone can tell me how to ,and better have a simple example vi. Thanks in advance!
CHR$(13) is the ASCII code for Carriadge return. LabVIEW has the same syntax as C. The ASCII code for Carriadge return in C is \r. To send this character to the serial port, create a string control (or constant). Right click on it and choose "'\' Codes Display". You can now type your command like this: "?R\n".
Here are some of the C ASCII codes: - \r : carriadge return (hex 13) - \n : line feed (hex 10) - \t : tab (hex 09) - \s : space (hex 20)