View source for DR780 High-Performance Channel Interface

The '''DR780 High-Performance Channel Interface''' provided a high-performance [[parallel interface]], the [[DR32 Device Interconnect]] (DDI), for the [[VAX-11/780]], connected to its [[Synchronous Backplane Interconnect]]. The DR32 may be used to connect to high-speed customer equipment; alternatively, two may be used to connect two /780's to each other.

A maximum of one DR780 was supported per machine; it could not be installed in a machine which had a [[MA780 Multiport Memory Option]]. The DR780 was implemented on four [[DEC card form factor|extended hex]] cards, which mounted in a custom 6-slot [[backplane]] ([[DEC part number]] 70-16896-0-0); the backplane mounted in one 'Option Panel Space' in the [[Central Processing Unit|CPU]] [[cabinet]]. The boards were:

{| class="wikitable"
! Slot !! Board !! Acronym !! Function
|-
| 1 || M8296 || DSC || SBI Control Module
|-
| 2 || M8297 || DCB || Control Board
|-
| 3 || M8298 || DUP || Microprocessor
|-
| 4 || M8299 || DSM || Silo Module
|}

One slot (5) is unused, and one slot (6) is used (on the back of the backplane) to hold a hex M9046 DR780 Paddle Card, which carries the DR780 input/output on three BC06R [[flat cable]]s to an 'External I/O Panel' in the back of the cabinet. From there, a BC06V cable connects to the user equipment.

{{semi-stub}}

==See also==

* [[DR750 Parallel Interface]]

==Further reading==

* ''DR780 User's Guide'' (EK-DR780-UG) - not available online
* ''DR780 Technical Description'' (EK-DR780-TD) - ditto
* ''DR780 Field Maintenance Print Set'' (MP00835)

==External links==

* [https://archive.org/details/digital_mast_1_10_5 Modular Approach to Systems Test] - contains a section on the DR780 (on pp. 3-20 of the PDF); includes detailed installation instructions
* [http://bitsavers.org/pdf/dec/vax/780/EK-SI780-IN-002_VAX-11_780_Installation_Manual_198201.pdf VAX-11/780 Installation Manual] (EK-SI780-IN-002) - contains a section on the DR780, Chapter 6 (on pp. 53-62 of the PDF)
* [http://bitsavers.org/pdf/dec/vax/780/DEC_VAX-11_780_Dual_RK07_System_Config_198101.pdf Dual RK07 Disk-Based VAX-11/780 System Configuration] - contains a brief description of the DR780
* [http://bitsavers.org/pdf/dec/vax/780/DEC_VAX-11_780_RP06_TE16_TU77_System_Config_198004.pdf RP06/TE16 and RP06/TU77 Based VAX-11/780 System Configuration] - ditto

[[Category: DEC Parallel Interfaces]]
[[Category: SBI]]