AT&K Flow Control

The &K command enables you to select the type of flow control used between your modem and the local computer when asynchronous mode is selected.You may want to do this to prevent possible data loss resulting from buffer overflow.

Using flow control guarantees that data buffers in your modem and computer won’t overflow.Your modem and your terminal or computer must be using the same type of flow control.

Flow control is only available when your modem is configured for constant speed mode or reliable or auto-reliable modes and is operating in on-line state.

Flow control will be ignored when your modem is configured for variable speed mode (AT\N1) or is in local command state.

WARNING

XON/XOFF flow control must not be selected when you are using XModem, YModem and SEAlink file transfers. XON/XOFF flow interferes with the operation of these file transfer protocols and will cause unreliable operation.

Options

AT&K0

Flow control disabled

AT&K3

RTS/CTS (hardware) flow control

 

The modem and computer use the CTS (Clear to Send) and RTS (Request to

 

Send) signals on the RS-232 serial connection to control data flow.

AT&K4

XON/XOFF (software) flow control

 

The modem and computer use the XON and XOFF characters (DC1 and

 

DC3) to control the flow of data.

AT&K5

Transparent XON/XOFF flow control

 

The modem and computer encode and decode XON and XOFF characters

 

which are part of the data stream.

 

Transparent XON/XOFF provides reliable operation when using file transfer

 

protocols.

AT&K9

Failsafe flow control

 

When the modem’s data buffer approaches maximum capacity, the modem

 

will lower the CTS signal. If the computer subsequently sends more than 60

 

(S82) characters to the modem, the modem will send an XOFF character to

 

the computer.

 

When the modem is ready to accept more data from the computer it will

 

assert CTS and, if an XOFF was sent by the modem, will send an XON

 

character to the computer.

 

Failsafe flow control only affects data being transmitted from the computer

 

to the modem. Flow control is not supported for data being transmitted by

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Telenetics 56 manual AT&K Flow Control, AT&K0, AT&K4, AT&K5, AT&K9