User`s guide

COMSPHERE 3821Plus Modem

3-42 January 1999 3821-A2-GB20-40

Table 3-9

(4 of 5)

V.42/MNP/Buffer Configuration Options

Mdm/Mdm FlowCtl: Disable

Nxt Disable Enable

This configuration option only appears if Async/Sync Mode is configured for Async and the Flow Control

configuration option is configured for XON/XOFF.

Modem-to-Modem Flow Control. If a modem’s buffers begin to fill due to data it is receiving from the remote modem, but

is not passing on to the DTE, it can issue XON/XOFF flow control characters to the remote modem. This only applies if

Buffer (nonerror control) mode is selected. If Error Control mode is enabled, flow control between the modems will

happen automatically, regardless of the setting of this configuration option.

Disable – Modem does not respond to XON and XOFF characters received over the VF line. Also, the modem will not

transmit an XOFF character to the remote end if its receive buffers are full.

Enable – Modem stops transmitting data to the remote modem if it receives an XOFF character over the VF line. An

XON character will enable data transmission. Also, the modem will transmit an XOFF character to the remote end if its

receive buffers are full. Select this setting if the DTE rate is less than the VF line rate or if the DTE must frequently stop

the flow of data to process it.

The factory default is Disable.

AT command equivalent is \G

Break Buffr Ctl: Keep_Data

Nxt Keep_Data Discard_Data Discard_Brk

This configuration option only appears if Async/Sync Mode is configured for Async.

Break Buffer Control. Determines if data stored in the modem’s buffer is saved or discarded when the DTE issues a

break sequence.

Keep Data (Nondestructive mode) – Saves the data in the buffer in both the local and remote modems.

Discard Data (Destructive mode) – Empties the data buffer. Only buffers in the same direction of travel as the break are

discarded.

Discard Break – A break received from the DTE is ignored by the modem and not sent across the link.

The factory default is Keep Data.

NOTE: This configuration option is ignored if the Break Forces Escape configuration option (see DTE Dialer

configuration options group) is enabled.

AT command equivalent is \K

Send Break Cntl: Data_First

Nxt Data_First Break_First

This configuration option only appears if Async/Sync Mode is configured for Async.

Send Break Control. Determines what is sent from the modem first, data or break if a break sequence is sent from the

DTE.

Data First (Nonexpedited) – A break is treated as a data character and is sent in the order it was received. This is also

known as Nonexpedited mode.

Break First (Expedited) – A break is sent before the data currently in the buffer. This is also known as Expedited mode.

The factory default is Data_First.

NOTE: This configuration option is ignored if the Break Forces Escape configuration option (see DTE Dialer

configuration options group) is enabled.

AT command equivalent is \K