DR11-B parallel interface

The DR11-B was a parallel interface for the UNIBUS which used DMA to transfer data.

Implementation

It was constructed from a number of smaller Flip Chips which were installed in custom 4-slot system unit backplane. The extant DR11-B documentation does not show either the modules used in the DR11-B, or their locations in the backplane.

The modules are:

• M112 - 10 x 2-input NOR gates
• M113 - 10 x 2-input NAND gates
• M116 - 6 x 4-input NOR gates
• M205 - 5 x 'D' flip flops
• 2 x M208 - 8-bit buffer / shift-register
• M239 - 3 x 4-bit counter/register
• 2 x M611 - High speed power inverters
• M796 - UNIBUS Master Control
• M7821 - Interrupt Control
• M7219 - Bus Interface

The M239's are used to hold the Status and Command Register.

The M7219 is a quad card; the others are all single. (The M796 and M7821 are extended length; the others are all standard length.)

Connection to the user device is via either a pair of M957 Split-Lug Cable boards, or via an M9760 (dual) Twisted Pair Cable Connector board. The M9680 (dual) board is a loopback test board, which can be used in place of the user connection board(s).