USRobotics V.34 user manual For users whose data does not include XON/XOFF

COURIER HIGH SPEED MODEMS

	NOTE: Because of the risk described in the above
	warning, the settings that follow are only recommended
	for users whose data does not include XON/XOFF
	control characters.
&I1	The Courier acts on your typed XON/XOFF commands,
	<Ctrl>-S or <Ctrl>-Q, and passes them to the remote
	computer. Use in ARQ mode only, but keep in mind that
	the XON/XOFF characters sent to the remote computer
	may interfere with XON/XOFF signaling between the
	remote computer and remote modem. See &I2.
&I2	The Courier acts on your XON/XOFF commands, but
	removes them from the data stream instead of passing
	them to the remote computer. This ensures that the
	remote computer does not confuse your XON/XOFF
	characters with those from its attached modem. This is
	the recommended setting for ARQ mode.
	However, if the call is not in ARQ mode, there is no flow
	control on the phone link. If you send an XOFF to your
	modem and it stops passing data, it has no way to tell the
	remote computer and modem to stop sending for a
	while, and your modem's buffer may overflow. For more
	reliable control in non-ARQ mode, see &I5.
&I3	Hewlett Packard⎯Host mode. Applies only to modems
	attached to an HP mainframe that uses the ENQ/ACK
	protocol. Use in ARQ mode only. See Appendix G.
&I4	Hewlett Packard⎯Terminal mode. Applies only to
	modems attached to terminals in an HP system that uses
	the ENQ/ACK protocol. Use in ARQ mode only. See
	Appendix G.
&I5	This setting is designed to enable flow control on the
	phone link when the connection is not under error
	control. For this to work for you, the remote modem
	must also have &I5 capability.
	In ARQ mode, a Courier set to &I5 operates the same as
	it does when set to &I2. It acts on your XON/XOFF com-
	mands, but does not pass them to the remote system.
	The error control protocol enables the modems to control
	the flow of data on the phone link.

4-28 Data Mode Operations