D-Channel X.25

Since the PAD is not specified for 8 bit characters plus parity, do not set the local DTE’s parity to 8 bits plus parity. When the local DTE’s parity is set to 8 bits plus parity, the data output to the DTE and the PAD service signals cannot be guaranteed to be correct.

If the remote DTE is not stripping the parity before transmitting the data to the local PAD, the local PAD may not recognize the LF and CR characters (depending on the parity) for line feed insertion and padding purposes.

Table 12-27: Parity Treatment

Value

Description

0No parity checking or generation *

3Parity checking and generation

*default

Parameter 22: Page Wait

Parameter 22 allows for the paging of data transmitted by the PAD to the local DTE. This parameter specifies the number of allowed line feeds to be transmitted by the PAD to the local DTE before the PAD suspends data transmission to the local DTE. When the specified line count of data has been transmitted to the local DTE, the service signal PAGE is delivered to the local DTE to notify the user that the data is being displayed in page mode. Note that no service signal is transmitted to the local DTE if parameter 6 (control of service signals) is set to 0. No more data is delivered to the DTE until the user sends the XON (Ctrl Q) character to cancel the page wait condition. Upon cancellation of the page wait condition, the PAD resumes the transmission of data to the local DTE until the specified line feed count is reached again.

The page wait condition can be canceled by issuing the XON character; however, there are certain situations that can occur that would cause the PAD to automatically cancel the page wait condition. These are:

After the echoing of a line feed that was input by the user. If the echo parameter (parameter 2) is not enabled, the page wait will not be canceled.

After the line deleted PAD service signal (and all its associated line feeds) have been transmitted to the local DTE.

Upon leaving the PAD command mode after all the associated line feeds.

Upon receipt of a data forwarding condition. For example, if parameter 3 (selection of data forwarding character) designates carriage return as the data forwarding character, when a carriage return is received from the local DTE, the page wait is canceled and the data currently stored by the PAD is forwarded.

UTA220/UTA220k

12-33

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Northern UTA220/UTA220k manual Parameter 22 Page Wait