Difference between revisions of "DR11-M general-purpose interface"

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Revision as of 04:45, 13 May 2020

DR11-M board

The DR11-M general-purpose interface was a UNIBUS device controller which provided a pair of 16-bit parallel ports, both output-only. It was a quad format card (M7865), and used an SPC slot; it used programmed I/O.

The DR11-M is roughly an output-only version of the earlier DR11-C general device interface, but is not program compatible with the DR11-C.

Connection to the user's device is via a pair of 40-pin Berg connectors; each is controlled by a separate set of registers (identical for the two connectors).


The device's register and interrupt vector addresses are set by a pair of DIP switches. Unusually for a UNIBUS device, its interrupt priority is also set by the switches. Both the vector and priority may be read in the Control and Status Register.


The device has two pairs of control and buffer registers, which can be configured to any four sequential word locations in the I/O page; the first DR11-M is normally configured to addresses 764000-76406:

Register Abbreviation Address
Control and Status Register A DRCSRA 764000
Data Buffer Register A DBDBRA 764002
Control and Status Register B DRCSRB 764004
Datia Buffer Register B DBDBRB 764006