noun
start bit
In serial data transmission, the bit that signals the beginning of a character or data unit.
シリアル通信では、スタートビットの後にデータビットが続く。
In serial communication, data bits follow the start bit.
Variant with interpunct; less common in running text.
The stop bit marks the end of a data unit, while the start bit marks the beginning.
Borrowed from English 'start bit'.