Northern UTA220/UTA220k Manuel D’Utilisation

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UTA220/UTA220k
D-Channel X.25
PAD Select
This command establishes an X.25 virtual call connection 
through the ISDN packet handler to a remote host or device. 
The contents of the PAD select command determine the 
contents of the X.25 Call Request packet. The format can be 
in any of following three forms:
<facility request block> - <address block> <call
user data>
<facility request block> - <call user data>
<address block> <call user data>
The facility request block permits the user to request special 
services from the ISDN network. If more than one facility is 
specified, a comma must separate each facility. The end of the 
facility request block must be followed by the hyphen 
character.
The address block specifies the called Network User Address 
(NUA). The address cannot exceed 15 characters in length. 
Abbreviated or multiple addresses are not supported. 
The call user data field cannot exceed 12 characters in length 
(including spaces) and must be preceded by either the P or D 
character. Carriage returns and the + character are not 
considered part of the user data field because they are treated 
as PAD command delimiters.
Response:
COM - Indicates the virtual call is established.
ERR - Indicates the PAD is in an unknown mode that cannot 
allow the PAD select command, the PAD has been initialized 
in the off-line mode (i.e., no virtual call connection has been 
established), or the PAD select command is invalid due to a 
format error. Some PAD select format errors are as follows:
• The facilities block is not followed by the - character.
• The CUG facility is requested and two decimal digits are not 
specified.
• The RPOA facility is requested and four decimal digits are 
not specified.
• The address block length exceeded 15 characters.
• The call user data block is not preceded by the P or D 
character.
• The call user data block length exceeded 12 characters.
• An invalid facility is requested as the first facility in the 
facility request block. 
CLR xxx - Indicates the attempted call has cleared. The   xxx   
is the ASCII character cause code which specifies the reason 
the call attempt cleared (see PAD Clear Service Signals).