Serial transmission (COM port) protocol requires sending a group of bits at one time. You cannot just send one bit. Standard COM port settings must be either 7 or 8 data bits, 1 or 2 stop bits, etc... You have to group your bits 7 or 8 at a time. You could probably send a 0 byte or a 1 byte. This would be like sending 0000 0000 for a low bit and 0000 0001 for a high bit. Your receiving end would have to know how to interpret what you are sending if you choose this method. Of course you have to convert your byte into a string before sending to COM port. Wire a U8 data type to a Build Array input. Then wire the array output to a Byte Array to String input. The output of this function will be the character representation of your byte suitable for sending across a serial port.