jackolim wrote: > Is it possible to program using labview to output a 1MHz squareware > out from serial port of PC?
As I recall, if you continuously transmit the character 'U' with 8 data bits, no parity and 1 stop bit, TxD will generate a square wave at the baud rate frequency. If you can set your baud rate to 1 Mhz, more power to you. Unfortunately, I know that my reference on this subject is on a slip of paper somewhere in a box full of slips of papers. Many times, the baud rate generator used in serial ports is only approximate in frequency; this must be taken into acount if you have a more exacting application.
