DRV11-J High-Density Parallel Interface

DRV11-J board

The DRV11-J High-Density Parallel Interface was a QBUS device controller which provided four bi-directional 16-bit parallel ports. It was a dual format card (M8049). It used programmed I/O; the direction of each port was programmable. It was not program compatible with any other DEC parallel port controller.

Connection to the user's device was via a pair of 50-pin Berg connectors; PORTS A and B through the bottom connector (furthest from the insertion handles), ports C an D via the top. Data going out to the user's device was latched in the DRV11-J, so may be read at leisure; data coming in from the user's device was merely sampled by the DRV11-J, so must be held until it has been read.

Registers

The device had four pairs of control and buffer registers, which could be configured to any eight sequential word locations in the I/O page. The first DRV11-J was normally configured to addresses 764160-764176; the second to 764140-767756, the third to 764120-767736, and so on.

Register	Abbreviation	Address
Control and Status Register A	DRCSRA	764160
Data Buffer Register A	DRDBRA	764162
Control and Status Register B	DRCSRB	764164
Data Buffer Register B	DRDBRB	764166
Control and Status Register C	DRCSRC	764170
Data Buffer Register C	DRDBRC	764172
Control and Status Register D	DRCSRD	764174
Data Buffer Register D	DRDBRD	764176

See also

• DRV11 parallel interface