DA11-B DMA UNIBUS Link - Revision history

Jnc: built by CSS

2022-08-30T02:26:44Z

built by CSS

Jnc: /* External links */ +manual

2022-08-30T02:22:17Z

‎External links: +manual

Jnc: Pretty stubby, but has the basics

2022-01-13T22:21:23Z

Pretty stubby, but has the basics

New page

The '''DA11-B DMA UNIBUS Link''' allows two [[UNIBUS]]es to be directly connected; either single words, or blocks of up to 32K words, can be transferred. The channel is [[half-duplex]]. Although the DA11-B can ''generate'' [[interrupt]]s on either UNIBUS (in response to user commands given directly to it via its Control and Status Register), it cannot ''transfer'' interrupts (i.e. from one UNIBUS to the other).

In Block Mode, the DA11-B uses [[Direct Memory Access|DMA]] on the source bus to read words in the block, and then uses DMA on the other UNIBUS to write the data.

The DA11-B is built out of a pair of [[DR11-B parallel interface]]s, each taking a [[system unit]] [[backplane]] in each computer. An M7229 buffer module is installed in each DR11-B's user connection slot,
[[DEC edge connector contact identification|CD0]].

==Registers==

{| border=1
! Register !! Address
|-
|Word count Register || XXXX00
|-
|Bus Address Register || XXXX02
|-
|Control and Status Register || XXXX04
|-
|Data Buffer Register || XXXX06
|}

The first DA11-B in a system is usually assigned register addresses starting with 0772410.

{{semi-stub}}
==External links==

* [http://www.bitsavers.org/pdf/dec/unibus/EK-DR11B-TM-004_DR11-B_DA11-B_Manual_Sep74.pdf DR11-B/DA11-B manual] (EK-DR11B-TM-004) - the DA11-B is covered in Appendix C
* [http://www.bitsavers.org/pdf/dec/pdp11/handbooks/PDP11_PeripheralsHbk_1976.pdf pdp11 peripherals handbook] - the DA11-B is covered on pp. 83-87

[[Category: UNIBUS Machine Interfaces]]

@@ Line 3: / Line 3: @@
 In Block Mode, the DA11-B uses [[Direct Memory Access|DMA]] on the source bus to read words in the block, and then uses DMA on the other UNIBUS to write the data.
-The DA11-B is built out of a pair of [[DR11-B parallel interface]]s, each taking a [[system unit]] [[backplane]] in each computer. An M7229 buffer module is installed in each DR11-B's user connection slot,
+The DA11-B was produced by [[Digital Equipment Corporation|DEC]]'s Computer Special System division; it was built out of a pair of [[DR11-B parallel interface]]s, each taking a [[system unit]] [[backplane]] in each computer. An M7229 buffer module is installed in each DR11-B's user connection slot, [[DEC edge connector contact identification|CD0]].
 ==Registers==

@@ Line 30: / Line 30: @@
 ==External links==
 * [http://www.bitsavers.org/pdf/dec/unibus/EK-DR11B-TM-004_DR11-B_DA11-B_Manual_Sep74.pdf DR11-B/DA11-B manual] (EK-DR11B-TM-004) - the DA11-B is covered in Appendix C
 * [http://www.bitsavers.org/pdf/dec/pdp11/handbooks/PDP11_PeripheralsHbk_1976.pdf pdp11 peripherals handbook] - the DA11-B is covered on pp. 83-87
 [[Category: UNIBUS Machine Interfaces]]