First page Back Continue Last page Overview Graphics
Handshaking for asynchronous data transfer
The clock rates for sender and receiver may be quite different.
The sender needs to know whether the receiver has received the information.
Handshaking is a way to enable sender and receiver to coordinate data transfers.
Types of handshaking
- simple output
- simple strobe
- single handshaking
- double handshaking
For data transfer between two computers, the sending and receiving speeds on both ends are often different. Therefore, a mechanism is needed to make sure that the sender does not send a new byte before the previously-sent byte is received by the receiver. Even when the sender and receiver operate at the same speed, the sender may still want to know whether the receiver has indeed received the information. Handshaking provides a mechanism for addressing this issue. Handshaking usually uses two additional hardware lines, one is called “strobe” and the other is called “acknowledge”. The sender provides the strobe signal and the receiver provides the acknowledge signal.
Handshaking can be used in both parallel data transfer and serial data transfer.
We will study four different data transfer conventions: simple output, simple strobe, single hand shaking and double handshaking.