Knowledge Base FAQ Item #3100015

Q3100015: What is the difference between hardware flow control and software flow control?

Both are used for handshaking (see also FAQ item 3100010).

With Hardware Flow Control, the receiving device sends a positive voltage along a dedicated handshaking circuit as long as it is ready to receive. When the transmitting computer receives a negative voltage, it knows to stop sending data.

With Software Flow Control, the handshaking signals consist of special characters transmitted along the data circuits rather than along the hardware flow control circuits.