pysäytysbittien

Pysäytysbittien refers to "stop bits" in the context of asynchronous serial communication. These are bits added to the end of a data packet or character to signal the receiver that the transmission of that unit has concluded. In asynchronous communication, the transmitter and receiver do not share a common clock signal. Therefore, stop bits are crucial for synchronizing the receiver and preparing it for the next incoming start bit.

When a byte or character is transmitted serially, it is preceded by a start bit, which indicates the beginning of the data. This is followed by the data bits themselves, typically 5 to 8 bits. After the data bits, one or more stop bits are sent. These stop bits are usually represented by a high signal level on the communication line, contrasting with the low signal level typically used for the start bit and data bits.

The number of stop bits used is a configurable parameter in serial communication protocols. Common choices are one, 1.5, or two stop bits. Using more stop bits provides a larger margin of error for the receiver to resynchronize, especially at higher baud rates or in environments with potential signal degradation. The specific number of stop bits must be agreed upon by both the transmitting and receiving devices for successful communication. Without proper stop bits, the receiver might misinterpret the end of one data unit and the beginning of the next, leading to corrupted data.