Difference between revisions of "DR11-C general device interface"

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The '''DR11-C general device interface''' was a [[UNIBUS]] [[device controller]] which provided a pair of 16-[[bit]] parallel ports, one input, and one output. It was a [[DEC card form factor|quad]] format card (M7860), and used an [[Small Peripheral Controller|SPC]] slot; it used [[programmed I/O]].
 
The '''DR11-C general device interface''' was a [[UNIBUS]] [[device controller]] which provided a pair of 16-[[bit]] parallel ports, one input, and one output. It was a [[DEC card form factor|quad]] format card (M7860), and used an [[Small Peripheral Controller|SPC]] slot; it used [[programmed I/O]].
  
Connection to the [[user]]'s device is via a pair of 40-[[pin]] [[Berg connector]]s. A pair of optional single-width paddle cards (M971) may be connected via [[flat cable]]s.
+
Connection to the [[user]]'s device is via a pair of 40-[[pin]] [[Berg connector]]s. A pair of optional single-width paddle cards (M971) may be connected via [[flat cable]]s. Data going out to the user's device was latched in the DR11-C, so may be read at leisure; data coming in from the user's device was merely sampled by the DR11-c, so must be held until it has been read.
  
 
The DR11-C is the replacement for the earlier multi-board [[DR11-A General Device Interface]]. The DR11-C is slightly enhanced over the DR11-A (the -A does not have the CSR1/CSR0 bits).
 
The DR11-C is the replacement for the earlier multi-board [[DR11-A General Device Interface]]. The DR11-C is slightly enhanced over the DR11-A (the -A does not have the CSR1/CSR0 bits).

Latest revision as of 03:30, 13 May 2020

DR11-C board

The DR11-C general device interface was a UNIBUS device controller which provided a pair of 16-bit parallel ports, one input, and one output. It was a quad format card (M7860), and used an SPC slot; it used programmed I/O.

Connection to the user's device is via a pair of 40-pin Berg connectors. A pair of optional single-width paddle cards (M971) may be connected via flat cables. Data going out to the user's device was latched in the DR11-C, so may be read at leisure; data coming in from the user's device was merely sampled by the DR11-c, so must be held until it has been read.

The DR11-C is the replacement for the earlier multi-board DR11-A General Device Interface. The DR11-C is slightly enhanced over the DR11-A (the -A does not have the CSR1/CSR0 bits).

Registers

The device has three control and buffer registers, which can be configured to any three sequential word locations in the I/O page; the first DR11-C is normally configured to addresses 767770-767774:

Register Abbreviation Address
Control and Status Register DRCSR 767770
Output Buffer Register DROUTBUF 767772
Input Buffer Register DRINBUF 767774

In the register contents (below), bits which are read/write or unused are shown in normal font, those which are read-only are in italics.

Status Register (DRCSR)

REQ B Unused REQ A INT ENB A INT ENB B Unused CSR1 CSR0
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
  • REQ B - Request B - Signal from user's hardware which can be tested, or cause an interrupt (below)
  • REQ A - Request A
  • INT ENB A - Interrupt Enable A - When set, allows setting REQ A to cause an interrupt
  • INT ENB B - Interrupt Enable B
  • CSR1 - Signal to user's hardware (on connector 1)
  • CSR0 - Signal to user's hardware (on connector 2)

Output Buffer Register (DROUTBUF)

OUT15 <-> OUT0
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Input Buffer Register (INBUF)

IN15 <-> IN0
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00