Software flow control
lastmod 2024-10-02created 2024-10-021 edits
Software flow control is a method of flow control used in computer data links, especially RS-232 serial. It uses special codes, transmitted in-band, over the primary communications channel. These codes are generally called XOFF and XON (from "transmit off" and "transmit on", respectively). Thus, "software flow control" is sometimes called "XON/XOFF flow control". This is in contrast to flow control via dedicated out-of-band signals — "hardware flow control" — such as RS-232 RTS/CTS.
XON/XOFF
Flow Control Xon/Xoff is a feature used for control when a host and a device communicate.
In asynchronous communication the two sides are not matched in speed, so one side may send too fast.
So when the receiver's buffer is full, it sends an Xoff signal. Then, once the buffer contents have been caught up, it sends an Xon signal again to resume communication
See also
- ASCII
- ANSI escape code (Terminal Control Escape Sequences)
- RS-232
- Serial Communication
- TTY
- ANSI escape code
- Terminfo
- Bash