RFC 311 UNKNOWN HARDWARE · TERMINALS · I/O

New Console Attachments to the USCB Host

An interface for connecting many device types to the UCSB host

On rfc-editor.org ↗
PUBLISHED
February 1972
AUTHORS
R.F. Bryan
STREAM
Legacy
DOI
10.17487/RFC0311

RFC text

Original text · RFC Editor View on rfc-editor.org ↗
                                                  UCSB Computer
NETWORK WORKING GROUP                             Research Lab.
REQUEST FOR COMMENTS # 311                        Roland F. Bryan
NIC #9341                                         29 February 1972


                NEW CONSOLE ATTACHMENTS TO THE UCSB HOST



   The MLC/360M
   ---------------

   The UCSB 360-75 is equipped with an interface unit that allows
   attachment of any type of I/O device to the Multiplexor Channel and
   for that device to be operated by program control as though it were a
   standard IBM Control Unit.  The interface, referred to as the
   Multi-Line Controller/360M (MLC/360M), operates on the Multiplexor
   Channel and provides 32 independently addressed I/O connections that
   are grouped into 16 pairs to accommodate full- duplex I/O operation.
   Each input group has a 16-bit input buffer plus related synchronizing
   and control logic to make it a stand-alone control unit on the 360
   channel.  Similarly, each output group has a 32-bit buffer plus logic.
   Attachment is achieved by connection through a data-set type connector
   and I/O signal levels conform to EIA standards (RS-232 Spec.).


   Both the I/O group hardware and the supporting software for the
   MLC/360M are readily modified to produce any variations required for
   attachment and operation of non-standard devices.


   Since our primary support was for 201B data-sets at 2400 baud, we
   first implemented the 16 I/O group pairs to accommodate this type of
   modem in our time-shared user environment.  The I/O groups have now
   been variously modified to support a wide range of applications, from
   300 baud acoustic coupled use to 9600 baud for multi-station classroom
   operation.



   New Consoles
   ---------------


   In addition to our standard attachments, which are mostly Culler-Fried
   graphic display consoles and educational classrooms
   using such consoles, we have a Tektronix 4002A and an NIH General
   Purpose Graphics Terminal (GPGT).


   The Tektronix terminal can now be operated on the ARPANET and will
   provide our users with upper and lower case ASCII for easier operation
   with other sites.  A report on this console's capability will be
   forthcoming.


   The GPGT was developed by the University of IOWA for use in
   Bio-Medical applications.  The unit is a delay-line refreshed video
   display with graphic capability and is the only dynamic type display
   in use on our host computer at present.  We are evaluating its
   performance in our On-Line System environment.  Since a user at this
   terminal is also able to reach into the network, we will have some
   future comments on its operation for interested persons.













       [ This RFC was put into machine readable form for entry ]
       [ into the online RFC archives by BBN Corp. under the   ]
       [ direction of Alex McKenzie.                   12/96   ]

ISO Plain Language

On this page
PROBLEMUCSB wanted its IBM 360/75 to connect to a range of terminals and other input/output devices.
MECHANISMThe MLC/360M provides independently addressed input and output connections on the computer's Multiplexor Channel, using EIA signal levels.
WHAT THE INTERFACE PROVIDESThe notice describes the interface and reports its use with different modems and display terminals.

§1The MLC/360M Interface

The Multi-Line Controller/360M is an interface unit attached to the Multiplexor Channel of UCSB's 360. It provides 32 independently addressed I/O connections arranged in 16 pairs for full-duplex use. Each input group has a 16-bit buffer, and each output group has a 32-bit buffer.

The interface gives the computer many separate paths for sending and receiving data. The paired paths can carry input and output at the same time.

§2Adaptable Device Connections

Devices connect through a data-set type connector, and the I/O signal levels follow the EIA RS-232 specification. The notice says both the hardware groups and their supporting software can be changed to accommodate non-standard devices.

The first implementation supported 201B data-sets at 2400 baud in a time-shared environment.

The interface uses RS-232 signal levels and can be adjusted for devices that do not fit its original setup. It first supported 201B data-sets.

§3Terminals and Other Uses

UCSB had modified I/O groups for a range of uses, from 300-baud acoustic-coupled connections to 9600-baud classroom operation. The notice also describes a Tektronix 4002A terminal that could use upper- and lower-case ASCII and a General Purpose Graphics Terminal that UCSB was evaluating in its online system.

UCSB adapted the interface for both slow and faster connections. It also used it with text and graphics terminals.