Flow Control - WAGO SPEEDWAY 767 Series Manual

74 Serial Interface
9.3.2

Flow Control

For a configuration as an RS-232 interface, there is the option of hardware flow
control via RTS/CTS. Alternatively, flow control via XOn/XOff can be activated.
Once flow control has been selected, the module takes over generation of the
required signals on the interface.
The status of the CTS line is transferred to the control unit in the status byte (see
input process image) for possible evaluation. For flow control via XOn/XOff, the
CTS/XOff bit is set once an XOff tag has been received.
The RTS line of the interface can be controlled via the control byte (see output
process image) independent of the module software. For flow control via
XOn/XOff, setting the RTS bit causes the XOff to be sent. When the RTS bit is
reset by the control unit, XOn is sent. It should be noted that the module software
controls the RTS function independent of the control unit as soon as the level of
the internal buffer requires it.
767-5203 Serial Interface (RS-232, RS-422/-485)
WAGO-SPEEDWAY 767
Manual
Version 1.1.0