period dimis ale J

Figure $4\mathrm{.}34$ Asynchronous transmission

without the addition of control information. But it is cheap and effective, two advantages that make it an attractive choice for situations such as low$-$speed communication. For example, the connection of a keyboard to a computer is a natural application for asynchronous transmission. A user types only one character at a time, types extremely slowly in data processing terms, and leaves unpredictable gaps of time between characters.