;--	DK:DIALUP.TXT   DATE: 3-MAY-86   TIME: 13:28

		Maarten van Swaay		maarten@ksuvax1.BITNET
		Dept. of Computer Science
		Nichols Hall
		Kansas State University
		Manhattan, Kansas 66506

DIALUP is a front end for terminal emulators that handle communication with
a remote host over dialup lines. It runs under RT11V4.

DIALUP should not require modification of existing emulators: it is designed
to be invoked from a command file that will subsequently start the appropriate
emulator. DIALUP returns exception reports to monitor level by discarding or
replacing the command file that called DIALUP. Therefore DIALUP need not be
aware of the emulator for which it is establishing a connection. Furthermore
it allows the user to control the consequences of DIALUP exceptions by means
of command files, without any need to modify either DIALUP or emulators.

Version 1.5 takes one of three exit paths:
Failure to acquire or control specified LUN:	discard command file
Failure to establish link to remote host:	replace command file
						with SY:DIALUP.ABT
Successful connection to remote host:		continue command file

Input lines to DIALUP must consist of a string to be sent to the modem, then
a separator character (default is caret <^>), then the expected single-digit
response from the modem. That implies that command strings will normally
include the command ATV0 to set the modem into terse mode.

A line containing the separator character as the first character sends the
ESCAPE sequence (+++) to the modem, surrounded by 2-second idle periods, to
reset the modem to command mode. The escape sequence is ignored by the modem
if it is already in command mode.

A null input line is ignored by DIALUP.

Any unexpected return from the modem will abort DIALUP, with the JSW chain bit
set, R0=0, and the string defined at KMNCMD delivered to KMON as its next
command. That will discard the remainder of any earlier command file.

DIALUP provides for redefinition of three symbols in a preamble file:

LUNREM	= xx	selects LUN connected to modem port.	Default = 2
TIMOUT	= xx	sets patience for modem response time.	Default = 30 seconds
CSEP	= 'x	defines command separator character.	Default = '^

Example command files for use with US ROBOTICS PASSWORD modem (HAYES
protocol), with comments added in lower-case:

! DK:HOST1.COM		command string to start a session with HOST1
R DIALUP
^			reset modem to command mode
ATV0T^0			tone-dial, terse response, expect response of 0
ATD 765-4321 ^1		dial up, expect response of 1
^C			dismiss DIALUP
R EMUL1			start emulator
LOGON.307		text consumed by emulator, defines a file
			containing logon dialog

! SY:DIALUP.ABT		invoked on failure to establish connection
R DIALUP		restart DIALUP for manual (diagnostic) input
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