Using the Eicon Host PAD and Eicon Terminal PAD

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This section explains how to prepare and test the Eicon Host PAD devices and includes the available stty settings for the Eicon Host PAD tty devices and their equivalent X.3 PAD parameters. It also provides information on configuring the Eicon Terminal PAD using the cu and uucp commands.

For more information on X.3 PAD parameters, see X.3 PAD Parameters.

 
Quick Reference

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The following list is a quick reference of Eicon Host PAD and Eicon Terminal PAD commands:

Displaying Status Information

hpad -h

hpad [-a][-v]

hpad [-v][devicename ...]

tpad -h

tpad [-v][devicename ...]

Loading Configuration Information

hpadcfg -h

hpadcfg [-v] [devicename ...]

hpadcfg [-p port][-a DTE][-f facility][-u userdata]

         [-C cfgfile] devicename ...

tpadcfg -h

tpadcfg [-p port][-l profile][-A tpaddir_entry] [-N][-L|-R]

         [-C cfgfile] devicename ...

Restoring Status

hpadload -h

hpadload [-t|-c] [-C cfgfile]

tpadload -h

tpadload [-c][-t {c,d,p}][-C cfgfile][-D dirfile][-P profile]

Maintaining Calling Directory

tpaddir -h

tpaddir [-a called_DTE][-l local_DTE][-f facilities]

         [-u userdata][-x parameters][-D dirfile][name...]

tpaddir -r [-D dirfile] name...

Maintaining X.3 Parameter Profiles

tpadprof -h

tpadprof [name...]

tpadprof [-x parameters][-s comment][-P profile][name...]

tpadprof -r [-P profile] name...

Information about all of these commands are available online. For information on how to access these commands, using an HTML browser, see For More Information.

 
Configuring Eicon Host PAD Devices

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Once the Eicon Host PAD driver has been installed and configured, it may be necessary to change the setup of the various Eicon Host PAD tty devices. In most cases, the default setup for the Eicon Host PAD devices should suffice. The following steps describe how to change the default terminal type and parity settings:

 
Testing Eicon Host PAD Devices

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Once the system has been rebooted and is running in multi-user mode, you should test an Eicon Host PAD connection as follows:

Note: Eicon Host PAD tty devices are disabled by editing /etc/inittab and changing the Eicon Host PAD device respawn flags to off.

You can test both the Eicon Host PAD Driver and the Eicon Terminal PAD Driver by connecting the two together over an actual X.25 network.

Two Eiconcards, or one multi-port Eiconcard, may be connected back to back, so that X.25 communications is used without the need for connection to an X.25 network. A null-modem cable must be connected between the two ports. In addition, one port must be set up as DCE with internal clocking and line speed set, and the other as DTE with external clocking.

Once the Eicon Host PAD driver is properly installed and at least one device has been tested, the Eicon Host PAD tty devices are ready to be used. Several Eicon Host PAD commands are provided for configuring Eicon Host PAD devices and checking their status. For more information on these commands, see the online documentation. For information on accessing online documentation, see For More Information.

 
stty/X.3 PAD Parameters

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The Linux stty command allows the Eicon Host PAD to change the setup of the remote Eicon Terminal PAD when the two are connected over an X.25 network.

Parity generation and checking is implemented in only the Eicon Host PAD driver. No X.29 packet is sent to the Eicon Terminal PAD to set parameter 21. If the terminal must use a 7-bit word size and even parity, set the Eicon Host PAD to use the stty settings cs7 parenb -parodd.

 
Using tpad with cu and uucp

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This section provides information on the configuration of the Eicon Terminal PAD for use by the Linux commands cu and uucp. Several examples that demonstrate the use of cu and uucp for making calls to a remote system are also included.

The Eicon Terminal PAD driver is used to make outgoing uucp calls. The uucp configuration files must be set to your specific requirements before you make a call. For information on configuring these files, see The uucp Configuration Files.

X.28 is a CCITT recommendation that defines the messages that a terminal can send to a PAD. The X.28 PAD command signals may be entered in uppercase or lowercase. Before any PAD command interpretation is performed, all control characters, including DEL and spaces, are stripped from the editing buffer.

For uucp, the connection and login must be automated. When the PAD is started, the PAD Identification PAD service signal is sent, followed by a prompt. The standard prompt is the "*" (asterisk) character. The Prompt PAD service signal will be displayed if the initial PAD parameter 6 has value 4 set (that is, equals 4 or 5). Therefore, the first Expect string is "*". The Send string should be a call request string that contains no intervening spaces.

Note: You can include spaces in a call request string if you enter them in hexadecimal or octal format (e.g., a space is \040, the "C"-like escape sequence for octal 40).

 
The cu Commands

You can use the following cu commands with the configured Eicon Terminal PAD devices.

<empty line>

When a virtual call is established, a blank command line causes a return to the data transfer state. Otherwise, the blank line is ignored.

Selection PAD command signal

The Selection PAD command signal syntax consists of a facility request block or an address block, or both, optionally followed by a call-user data field.

This standard PAD command signal, defined in recommendation X.28-3.5.15, is not implemented in this version of the PAD.

Note: The commands listed below are not case-sensitive. For example, you can enter the call or CALL command.

call

The call PAD service signal provides the only outgoing call mechanism.

*call address [/facilities [/userdata]]

This establishes a call to the given X.25 address, with the specified facilities and call-user data. Valid X.25 addresses are strings of 1 to 15 digits. Facilities are numbers from 0 to 255, separated by commas. The facilities field may be empty, or contain up to 109 octets.

The call-user data is a set of numbers from 0 to 255, separated by commas and/or quoted strings. If the call-user data field starts with a minus symbol (-), the standard PAD protocol identifier 1,0,0,0 is suppressed in the call-user data. Up to 16 octets of call-user data are allowed (including the PAD protocol identifier), but this maximum is 128 octets when used with the fast select facility. If a virtual call is already established when this command is invoked, the error message Already connected is displayed. This PAD command signal is provided as an extension to the standard PAD functionality.

Examples

*call 324576

*call 092341 /1,1

*call 324543123 /1,0,2,1 /"login"

*call 234512343 // "uucp"

*call 34657332 /1,0 /-1,0,0,1,"bill"

clr

Clear virtual call. If no virtual call is established when this command is invoked, the error message No connection is displayed.

*clr

conn name

Connect to given name. The name is a PAD directory entry that describes the called DTE, its X.25 address, the facilities, the call-user data, and the X.3 parameters to be used (see the tpaddir command online). This PAD command signal is provided as an extension to the standard PAD recommendation.

*conn host1

exit, logout, quit

Exit PAD. This command forces the tty software to simulate a loss of carrier detect signal and forces the Eicon Terminal PAD driver to read and write return zero (end of file). Ultimately, all processes currently using the Eicon Terminal PAD will close the Eicon Terminal PAD device file. This PAD command signal is provided as an extension to the standard PAD recommendation.

*exit

id

Display PAD identification PAD service signal. The format of the message is:

tpad device profile profile port port

where device is a 1, 2, or 3-decimal-digit number representing the decimal value of the minor device number; profile is the initial X.3 profile identifier for the device; port is the device's initial port number in decimal. This PAD command signal is provided as an extension to the standard PAD recommendation.

*id

tpad 0 profile 'uucp'

int

Send interrupt packet. An interrupt data packet with one byte of call-user data set to zero is sent over the X.25 virtual circuit. If no virtual call is established when this command is invoked, the error message No connection is displayed.

*int

port [port]

Set physical port. This command sets the physical port on which the communications will take place. Normally, ports 1-255 are used. If you do not specify a port, the current port number is displayed. To re-assign a port, include a decimal number with the port command. This PAD command signal is provided as an extension to the standard PAD recommendation.

*port

1

*port 2

*port

2

prof [profile identifier]

Set X.3 Profile. Set the X.3 PAD parameter profile to that of the specified profile identifier. If no profile identifier is specified, display the currently selected profile identifier. If the specified profile identifier is not known, the error message Profile not found is displayed.

Three standard profiles are provided: uucp (default), 90, and 91. The following lists the PAD parameter values for each of these profiles:

*prof

90

*prof uucp

*prof

uucp

par? [par,par,...], par [par,par,...]

Display X.3 parameters. Display the current value of the specified X.3 PAD parameters. If no parameter is specified, all parameters are displayed. If a specified parameter reference is invalid, it is displayed with its value specified as inv. The two commands are treated identically. The PAD command signal par is provided as an extension to the standard PAD recommendation.

reset

Reset virtual circuit. If no virtual call is established when this command is invoked, the error message No connection is displayed.

set [par:val,par:val...]

Set the specified X.3 PAD parameters (par) to the specified values (val). If no par:val is specified, the PAD parameters are set to the value of the current profile identifier. If a specified parameter reference and/or value is invalid, it is displayed with its value specified as inv.

*set 1:0,2:1

*set 1:1,2:3

par 2:inv

*set 2:0

set? [par:val,par:val...]

Set and display the specified X.3 PAD parameters (par) and values (val). If no par:val is specified, the PAD parameters are set to the value of the current profile identifier. If a specified parameter reference and/or value is invalid, it is displayed with its value specified as inv.

*set? 1:0,2:1

par 1:0, 2:1

*set? 1:1,2:3

par 1:1, 2:inv

*set? 2:0

par 2:0

stat

Display the status of the virtual call, which may be either engaged or free.

 
X.3 PAD Parameters

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The uucp Standard profile (similar to the X.3 Standard profile) should be used when uucp transfers are to be made with the Eicon Terminal PAD. In particular, the X.3 PAD parameter 12 must be zero (no flow control of the PAD by the start-stop mode DTE), otherwise the X-ON and X-OFF characters will be interpreted by the PAD, making binary data transfer impossible.

You may need to modify some of the PAD parameter values. With the exception of timer expiration (4:1), the PAD parameters should be set so that no data interpretation is done. The Recall character should be zero (1:0), Echoing off (2:0), no data forwarding character (3:0), no special character insertion (10:0, 13:0), no editing (15:0), no page wait (22:0). Hosts to which the Eicon Terminal PAD connects should send the appropriate X.29 set or set and read PAD messages when the tty mode is changed from canonical mode to raw mode. See your Linux documentation for a description of the stty command.

 
The uucp Configuration Files

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You must set up the configuration for your Eicon Terminal PAD devices before you can use them. To do this, you add or edit appropriate entries in the uucp configuration files. This must be done before calls are made with the Eicon Terminal PAD.

Examples are used to help clarify how these uucp configuration files are used. Names and other user-supplied items are chosen arbitrarily. To run these examples on your system, choose user-supplied names and items that are defined for your system.

The uucp configuration files are usually located in the /etc/uucp directory. Check your Linux documentation on uucp for the correct path on your system. There are several uucp configuration files including call, dial, dialcode, passwd, port, and sys. The example below uses the sys and port files.

 
Sys

In the sys file, add entries to define your connections. In the example below, the entry defines a uucp connection via the PAD. The connection is named 'pad' and can be called at "any' time using a device type of 'tpad' at speed '38400'. This entry may be used with cu or an interactive terminal-emulation program when direct user interaction is desired with the PAD.

system pad

time any

port tpad

speed 38400

 
Port

In the port file, add entries for each terminal tty line device.

port tpad

type direct

device /dev/tpadEt00

speed 38400

 
Using uucp and cu

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uucp implementations are very flexible. They can be customized to suit the various types of line connections and modems you use for uucp communications. Before running this example on your system, the uucp configuration files must be set up according to specific requirements.

In the following examples, "#" is the system prompt, "*" is the Eicon Terminal PAD prompt, and "$" is the remote system prompt.

Note: Verify that you have correctly configured the Eicon Terminal PAD device(s) before attempting to establish a connection. For example, you may need to assign ports using the tpadcfg -p command.

Example 1

Use the cu utility to login to a remote system. The pad entry of the Systems file connects you to the Eicon Terminal PAD. You may then call a remote system over an X.25 network: