HP 3000 Manuals HP 3000 Manuals
DTC/Terminal Access Enhancements
by Stephen Lin
Business Networks Division
DTC/Terminal Access introduced on XL Release 2.0 is a LAN-based
controller for asynchronous access to HP 3000 Series 900 systems. It
provides connections to terminals, PCs in terminal emulation mode, and
serial printers. Two types of network management are provided with XL
Release 2.0, PC-based and Host-based. In a PC-based network management
environment the product allows terminal users to access multiple HP 3000
Series 900 systems on the LAN. With the PC-based OpenView DTC Manager
software, a single operator is able to manage multiple DTCs on the LAN.
In a Host-based network management environment, the DTC continues to
provide simple and cost-effective asynchronous connections to a single HP
3000 Series 900 host.
Beginning with XL Release 2.1, the product has been enhanced to provide
the configuration for Native Language I/O (NLIO) support and more
flexible control of serial printers.
NATIVE LANGUAGE I/O SUPPORT THROUGHT NMMGR
All Datacomm product configurations are done through the configuration
utility NMMGR. To allow the support of NLIO, NMMGR is updated to contain
profile screen changes for both PC and Host-based configuration.
The field NLIO Device ? (Y/N) is added to each profile screen at the
branches DTS.PROFPC.profname in a PC-based configuration and
DTS.PROFILE.profname in a Host-based configuration. Profname is a device
profile name such as TR10D96, PR22D24, etc. The additional field is
included in the terminal profile screen as well as in the printer profile
screen.
To enable NLIO support simply change the field to "Y". The default is
"N" for backward compatibility.
The Datacomm configuration file NMCONFIG.PUB.SYS needs to be converted to
the 2.1 format. The conversion utility NMMGRVER must be run against
NMCONFIG after the system is updated or installed with the 2.1 FOS.
PRINTER CONTROL THROUGHT TTUTIL
Four standard printer type files, TT18, TT21, TT22, and TT26 were
included in XL Release 2.0 for general usage. Users can use the
Workstation Configurator utility, TTUTIL, to customize their own
terminal/printer type files to tailor for their particular asynchronous
devices.
In XL Release 2.1, TTUTIL has been enhanced to include two new fields in
the PRINTER CONTROL screen:
[ ] Status Requests: Efficiency Mode Enabled (Y, N)
[ ] Status Request Frequency (1 request per 1..250 writes)
These two fields provide flexible control in performing status requests
for printers. The first field (efficiency mode) provides the same
feature already found in MPE V/E FOS. The second field (frequency) is
newly created for MPE XL.
When efficiency mode is enabled, status requests are performed only at
FOPEN, FCLOSE, and device CLOSE. It is the same mode used for the
standard printer types TT21, TT22 and TT26 on MPE XL. (In terms of when
status requests are sent to the printer, TT21, TT22 and TT26 behave the
same way. However, TT26 will re-activate its timer up to 10 times if no
status reply is received from the printer. TT21 and TT22 will
immediately cause a Spoolee error if a status reply is not received
within 60 seconds.) When efficiency mode is disabled, a status request
is sent to the printer at the end of every write. It provides the same
functionality as printer type TT22 on MPE V/E.
NOTE TT22 on MPE XL and TT22 on MPE V/E have different behaviors in
terms of status requests sent. In essence, TT22 on MPE XL operates
in efficiency mode while TT22 on MPE V/E operates in non-efficiency
mode.
To further increase flexibility when efficiency mode is DISABLED, the
user can customize the status request protocol by selecting the status
request frequency. The figure configured determines when a status
request will be sent, in addition to the status requests sent at FOPEN,
FCLOSE and device CLOSE. A frequency "N" specifies that a status request
will be performed after every "N" writes. The value "N" ranges from 1
through 250. The frequency "1" specifies that status requests should be
sent at the same frequency as for TT22 on MPE V/E (i.e., at the end of
every record).
The default values for newly created printer types are efficiency mode
enabled and no value for status request frequency. When efficiency mode
is enabled the frequency field is automatically set to blank, since no
status requests will be performed after writes. When a termtype is
converted from MPE V/E (through TTUTIL), efficiency mode will depend on
the previous setting. However, if the efficiency mode is disabled, the
new frequency field will be interpreted as "1" and utilized by the
terminal I/O driver. This implies that a status request will be sent at
the end of every write.