UCSB Computer NETWORK WORKING GROUP Research Lab. REQUEST FOR COMMENTS # 311 Roland F. Bryan NIC #9341 29 February 1972
The MLC/360M
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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
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In addition to our standard attachments, which are mostly Culler-Fried graphic display consoles and educational classrooms
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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.
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