Northern UTA220/UTA220k Parameters and Values, Saving the X.3 Parameter Configuration, Clr Np

D-Channel X.25

	Table 12-4: PAD Clear Service Signals (Continued)
CLR RPE	Remote DTE procedure error detected by the remote DTE/DCE
	interface
CLR NP	Called DTE address not assigned to any DTE
CLR DER	Called number out of order or not responding
CLR DTE	Remote DTE cleared the call
CLR RNA	Called DTE not subscribed to reverse charging acceptance,
	allowing the called DTE to accept the calling DTE’s request for
	reverse charging (the reverse charge facility in the facility request
	field of the call request packet)

X.3 PARAMETERS AND VALUES

Just as the AT commands control some of the operating features of the TA, the X.3 parameters control the PAD’s operating features. These parameters are user configurable and remote configurable: the remote device can change the local PAD parameters to designate how the PAD handles the data.

Most X.3 parameters govern how the data displays because the data display depends on the type of local DTE or application. Other X.3 parameters govern PAD functions such as data forwarding (when to stop packeting the data received from the local DTE device and transmit the packet), editing, flow control, and service signal control.

Saving the X.3 Parameter Configuration

When the TA is first powered up, the X.3 parameters are set to the default (factory) settings (Table 12-5). PAD parameters can be modified using the set or set and read PAD commands. The PAD must be in the PAD command mode before the set or set and read commands can be executed. During a virtual call, the remote device can change the X.3 parameter configuration from the user's set configuration. To avoid the problems this may cause, the PAD saves the current settings of the X.3 parameters to RAM an X.25 virtual call is initiated. When the virtual call is disconnected, the saved X.3 parameter settings are restored. The PAD does not save the current X.3 parameter settings when the virtual call connection is established by the remote DTE.

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