CALL - Call Command


Command Line Formats
CALL
[CALL] [<facility>] [<called>[,[<calling>] [,<lcn>] ] ]
[CALL] <facility>D <user_data>
[CALL] <called>D <user_data>
[CALL] <facility><called>[,[<calling>] [,<lcn>] ] D<user_data>

Suffix Values
<facility>
One or more call parameter facilities that can be strung together on a command line and separated by commas; the last facility is followed by a hyphen (-).

<called> Represents the remote system address containing up to 15 digits (0-9)

<calling> Represents source address containing up to 15 digits (0-9)

<lcn> X.25 logical channel number (1-4095)

<user_data> Character string containing up to 12 ASCII characters

Result Codes
ERR
- Call cannot be placed due to call in progress; or virtual connection not established

CLR - Remote PAD cleared virtual connection; may be followed by a string of diagnostic characters

CON - Call connected; may be followed by a string of diagnostic characters

Description
The CALL command makes a virtual connection to a remote system. Once the PAD is configured, this is the primary command you will use. Once a physical connection to the X.25 network has been established, a virtual connection to the remote system is made with the CALL command. If the call is accepted by the remote system, the PAD enters the data transfer state. If the call is not accepted, a call cleared response is sent and the PAD remains in the PAD command state.

Call Facilities
In the CALL command formats, notice the <facility>field. This field specifies call facilities. A call facility is an optional parameter that can be specified to meet the network requirements, such as entering a network user ID (NUI), or indicating that charges are to be reversed (R).

When subscribing to a packet-switched network, you are informed of the required or permitted call facilities. To respond to your CALL command, different networks may require specific call facilities.

Any of the call facilities in the following chart can be entered with the CALL command. When two or more facilities are entered on a line, they are separated by commas. A hyphen (-) terminates the string, e.g., CALL R, N, -.

Call Facility Description
R
Instructs network that you accept charges for the call if requested to do so.

N <NUI>
Provides network with network user ID, identifying the caller to the network.

T <RPOA>
Specifies which networks the data packets take to their destination. Any number of addresses may be specified; each address is four digits (0-9). RPOA stands for Recognized Private Operating Agencies.

P <num>
Requested maximum packet size according to the following packet size-to-bytes conversions: P4=16, P5=32, P6=64, P7=128, P8=256, P9=512. If P is not specified, the default value (128) of National PAD Parameter 100 is used.

W <num>
Requested maximum window size (2-7). If W is not specified, the default value (2) of National PAD parameter 101 is used.

X <hex>
Hexadecimal data (0-9, A-F). Caution: Putting data directly into the facilities field of the call packet, specifies facility codes not directly supported by the modem.


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