TYAN S5556 Manual page 68

Flow Control
Flow Control can prevent data loss from buffer overflow. When sending data, if the
receiving buffers are full, a 'stop' signal can be sent to stop the data flow. Once the
buffers are empty, a 'start' signal can be sent to restart the flow. Hardware flow
control uses two wires to send start/stop signal.
None / Hardware RTS/CTS / Software Xon/Xoff
Data Bits / Parity / Stop Bits
Read only.
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